diff --git a/src/observer/catalog/catalog.cpp b/src/observer/catalog/catalog.cpp
index 367786a62..e47709921 100644
--- a/src/observer/catalog/catalog.cpp
+++ b/src/observer/catalog/catalog.cpp
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "catalog/catalog.h"
 
+namespace oceanbase {
+
 const TableStats &Catalog::get_table_stats(int table_id)
 {
   lock_guard<mutex> lock(mutex_);
@@ -20,4 +22,5 @@ void Catalog::update_table_stats(int table_id, const TableStats &table_stats)
 {
   lock_guard<mutex> lock(mutex_);
   table_stats_[table_id] = table_stats;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
diff --git a/src/observer/catalog/catalog.h b/src/observer/catalog/catalog.h
index 73d47d778..4d488700c 100644
--- a/src/observer/catalog/catalog.h
+++ b/src/observer/catalog/catalog.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/mutex.h"
 #include "catalog/table_stats.h"
 
+namespace oceanbase {
+
 /**
  * @class Catalog
  * @brief Store metadata, such as table statistics.
@@ -71,4 +73,5 @@ class Catalog
    * This map is currently not persisted and its persistence is planned via a system table.
    */
   unordered_map<int, TableStats> table_stats_;  ///< Table statistics storage.
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/catalog/table_stats.h b/src/observer/catalog/table_stats.h
index 475f47ea5..bf4b01bf6 100644
--- a/src/observer/catalog/table_stats.h
+++ b/src/observer/catalog/table_stats.h
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 /**
  * @class TableStats
  * @brief Represents statistics related to a table.
@@ -36,4 +38,5 @@ class TableStats
   ~TableStats() = default;
 
   int row_nums = 0;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/global_context.cpp b/src/observer/common/global_context.cpp
index da7120188..3747442c4 100644
--- a/src/observer/common/global_context.cpp
+++ b/src/observer/common/global_context.cpp
@@ -14,6 +14,9 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/global_context.h"
 
+namespace oceanbase {
+
 static GlobalContext global_context;
 
 GlobalContext &GlobalContext::instance() { return global_context; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/global_context.h b/src/observer/common/global_context.h
index acf5c3adf..e1be45471 100644
--- a/src/observer/common/global_context.h
+++ b/src/observer/common/global_context.h
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 class BufferPoolManager;
 class DefaultHandler;
 class TrxKit;
@@ -31,4 +33,5 @@ struct GlobalContext
   static GlobalContext &instance();
 };
 
-#define GCTX GlobalContext::instance()
\ No newline at end of file
+#define GCTX GlobalContext::instance()
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/ini_setting.h b/src/observer/common/ini_setting.h
index 74a35de3d..4ace65cb3 100644
--- a/src/observer/common/ini_setting.h
+++ b/src/observer/common/ini_setting.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 //! this document is used for ini setting
 
+namespace oceanbase {
+
 #define CLIENT_ADDRESS "CLIENT_ADDRESS"
 #define MAX_CONNECTION_NUM "MAX_CONNECTION_NUM"
 #define MAX_CONNECTION_NUM_DEFAULT 8192
@@ -25,3 +27,4 @@ See the Mulan PSL v2 for more details. */
 #define SOCKET_BUFFER_SIZE 8192
 
 #define SESSION_STAGE_NAME "SessionStage"
+}  // namespace oceanbase
diff --git a/src/observer/common/init.cpp b/src/observer/common/init.cpp
index a48b73499..52b972b39 100644
--- a/src/observer/common/init.cpp
+++ b/src/observer/common/init.cpp
@@ -32,6 +32,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 bool *&_get_init()
 {
   static bool  util_init   = false;
@@ -129,10 +131,7 @@ void cleanup_log()
   }
 }
 
-int prepare_init_seda()
-{
-  return 0;
-}
+int prepare_init_seda() { return 0; }
 
 int init_global_objects(ProcessParam *process_param, Ini &properties)
 {
@@ -140,10 +139,10 @@ int init_global_objects(ProcessParam *process_param, Ini &properties)
 
   int ret = 0;
 
-  RC rc = GCTX.handler_->init("miniob", 
-                              process_param->trx_kit_name().c_str(),
-                              process_param->durability_mode().c_str(),
-                              process_param->storage_engine().c_str());
+  RC rc = GCTX.handler_->init("miniob",
+      process_param->trx_kit_name().c_str(),
+      process_param->durability_mode().c_str(),
+      process_param->storage_engine().c_str());
   if (OB_FAIL(rc)) {
     LOG_ERROR("failed to init handler. rc=%s", strrc(rc));
     return -1;
@@ -236,3 +235,4 @@ void cleanup_util()
 }
 
 void cleanup() { cleanup_util(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/init.h b/src/observer/common/init.h
index 466415dbd..9bb82cff5 100644
--- a/src/observer/common/init.h
+++ b/src/observer/common/init.h
@@ -17,5 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/conf/ini.h"
 #include "common/os/process_param.h"
 
+namespace oceanbase {
+
 int  init(common::ProcessParam *processParam);
 void cleanup();
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/attr_type.cpp b/src/observer/common/type/attr_type.cpp
index e8af0084a..75aa910eb 100644
--- a/src/observer/common/type/attr_type.cpp
+++ b/src/observer/common/type/attr_type.cpp
@@ -8,10 +8,11 @@ EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 See the Mulan PSL v2 for more details. */
 
-
 #include "common/lang/string.h"
 #include "common/type/attr_type.h"
 
+namespace oceanbase {
+
 const char *ATTR_TYPE_NAME[] = {"undefined", "chars", "ints", "floats", "vectors", "booleans"};
 
 const char *attr_type_to_string(AttrType type)
@@ -32,12 +33,7 @@ AttrType attr_type_from_string(const char *s)
   return AttrType::UNDEFINED;
 }
 
-bool is_numerical_type(AttrType type)
-{
-  return (type == AttrType::INTS || type == AttrType::FLOATS);
-}
+bool is_numerical_type(AttrType type) { return (type == AttrType::INTS || type == AttrType::FLOATS); }
 
-bool is_string_type(AttrType type)
-{
-  return (type == AttrType::CHARS);
-}
\ No newline at end of file
+bool is_string_type(AttrType type) { return (type == AttrType::CHARS); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/attr_type.h b/src/observer/common/type/attr_type.h
index d1c07e3a2..8a73a201a 100644
--- a/src/observer/common/type/attr_type.h
+++ b/src/observer/common/type/attr_type.h
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 /**
  * @brief 属性的类型
  * @details AttrType 枚举列出了属性的各种数据类型。
@@ -29,3 +31,4 @@ const char *attr_type_to_string(AttrType type);
 AttrType    attr_type_from_string(const char *s);
 bool        is_numerical_type(AttrType type);
 bool        is_string_type(AttrType type);
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/char_type.cpp b/src/observer/common/type/char_type.cpp
index 6c93114a9..e98e77110 100644
--- a/src/observer/common/type/char_type.cpp
+++ b/src/observer/common/type/char_type.cpp
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/type/char_type.h"
 #include "common/value.h"
 
+namespace oceanbase {
+
 int CharType::compare(const Value &left, const Value &right) const
 {
   ASSERT(left.attr_type() == AttrType::CHARS && right.attr_type() == AttrType::CHARS, "invalid type");
@@ -48,4 +50,5 @@ RC CharType::to_string(const Value &val, string &result) const
   ss << val.value_.pointer_value_;
   result = ss.str();
   return RC::SUCCESS;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/char_type.h b/src/observer/common/type/char_type.h
index 74dab5092..9c6968f92 100644
--- a/src/observer/common/type/char_type.h
+++ b/src/observer/common/type/char_type.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/type/data_type.h"
 
+namespace oceanbase {
+
 /**
  * @brief 固定长度的字符串类型
  * @ingroup DataType
@@ -34,3 +36,4 @@ class CharType : public DataType
 
   RC to_string(const Value &val, string &result) const override;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/data_type.cpp b/src/observer/common/type/data_type.cpp
index 6df3fa6ac..71fda2765 100644
--- a/src/observer/common/type/data_type.cpp
+++ b/src/observer/common/type/data_type.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/type/data_type.h"
 #include "common/type/vector_type.h"
 
+namespace oceanbase {
+
 // Todo: 实现新数据类型
 // your code here
 
@@ -24,4 +26,5 @@ array<unique_ptr<DataType>, static_cast<int>(AttrType::MAXTYPE)> DataType::type_
     make_unique<FloatType>(),
     make_unique<VectorType>(),
     make_unique<DataType>(AttrType::BOOLEANS),
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/data_type.h b/src/observer/common/type/data_type.h
index 54f0f3dc0..cc7caaeca 100644
--- a/src/observer/common/type/data_type.h
+++ b/src/observer/common/type/data_type.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/type/attr_type.h"
 
+namespace oceanbase {
+
 class Value;
 class Column;
 
@@ -104,3 +106,4 @@ class DataType
 
   static array<unique_ptr<DataType>, static_cast<int>(AttrType::MAXTYPE)> type_instances_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/float_type.cpp b/src/observer/common/type/float_type.cpp
index 207f705a7..d35f116b0 100644
--- a/src/observer/common/type/float_type.cpp
+++ b/src/observer/common/type/float_type.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "storage/common/column.h"
 
+namespace oceanbase {
+
 int FloatType::compare(const Value &left, const Value &right) const
 {
   ASSERT(left.attr_type() == AttrType::FLOATS, "left type is not float");
@@ -30,8 +32,7 @@ int FloatType::compare(const Column &left, const Column &right, int left_idx, in
 {
   ASSERT(left.attr_type() == AttrType::FLOATS, "left type is not float");
   ASSERT(right.attr_type() == AttrType::FLOATS, "right type is not float");
-  return common::compare_float((void *)&((float*)left.data())[left_idx],
-      (void *)&((float*)right.data())[right_idx]);
+  return common::compare_float((void *)&((float *)left.data())[left_idx], (void *)&((float *)right.data())[right_idx]);
 }
 
 RC FloatType::add(const Value &left, const Value &right, Value &result) const
@@ -70,7 +71,7 @@ RC FloatType::negative(const Value &val, Value &result) const
 
 RC FloatType::set_value_from_str(Value &val, const string &data) const
 {
-  RC                rc = RC::SUCCESS;
+  RC           rc = RC::SUCCESS;
   stringstream deserialize_stream;
   deserialize_stream.clear();
   deserialize_stream.str(data);
@@ -92,3 +93,4 @@ RC FloatType::to_string(const Value &val, string &result) const
   result = ss.str();
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
diff --git a/src/observer/common/type/float_type.h b/src/observer/common/type/float_type.h
index 9bf0be848..2c63133e3 100644
--- a/src/observer/common/type/float_type.h
+++ b/src/observer/common/type/float_type.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/type/data_type.h"
 
+namespace oceanbase {
+
 /**
  * @brief 浮点型数据类型
  * @ingroup DataType
@@ -34,4 +36,5 @@ class FloatType : public DataType
   RC set_value_from_str(Value &val, const string &data) const override;
 
   RC to_string(const Value &val, string &result) const override;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/integer_type.cpp b/src/observer/common/type/integer_type.cpp
index 48f20f7df..9fa6cf0f4 100644
--- a/src/observer/common/type/integer_type.cpp
+++ b/src/observer/common/type/integer_type.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "storage/common/column.h"
 
+namespace oceanbase {
+
 int IntegerType::compare(const Value &left, const Value &right) const
 {
   ASSERT(left.attr_type() == AttrType::INTS, "left type is not integer");
@@ -33,21 +35,18 @@ int IntegerType::compare(const Column &left, const Column &right, int left_idx,
 {
   ASSERT(left.attr_type() == AttrType::INTS, "left type is not integer");
   ASSERT(right.attr_type() == AttrType::INTS, "right type is not integer");
-  return common::compare_int((void *)&((int*)left.data())[left_idx],
-      (void *)&((int*)right.data())[right_idx]);
+  return common::compare_int((void *)&((int *)left.data())[left_idx], (void *)&((int *)right.data())[right_idx]);
 }
 
 RC IntegerType::cast_to(const Value &val, AttrType type, Value &result) const
 {
   switch (type) {
-  case AttrType::FLOATS: {
-    float float_value = val.get_int();
-    result.set_float(float_value);
-    return RC::SUCCESS;
-  }
-  default:
-    LOG_WARN("unsupported type %d", type);
-    return RC::SCHEMA_FIELD_TYPE_MISMATCH;
+    case AttrType::FLOATS: {
+      float float_value = val.get_int();
+      result.set_float(float_value);
+      return RC::SUCCESS;
+    }
+    default: LOG_WARN("unsupported type %d", type); return RC::SCHEMA_FIELD_TYPE_MISMATCH;
   }
 }
 
@@ -77,7 +76,7 @@ RC IntegerType::negative(const Value &val, Value &result) const
 
 RC IntegerType::set_value_from_str(Value &val, const string &data) const
 {
-  RC                rc = RC::SUCCESS;
+  RC           rc = RC::SUCCESS;
   stringstream deserialize_stream;
   deserialize_stream.clear();  // 清理stream的状态，防止多次解析出现异常
   deserialize_stream.str(data);
@@ -97,4 +96,5 @@ RC IntegerType::to_string(const Value &val, string &result) const
   ss << val.value_.int_value_;
   result = ss.str();
   return RC::SUCCESS;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/integer_type.h b/src/observer/common/type/integer_type.h
index 9b6472e34..6a7528f60 100644
--- a/src/observer/common/type/integer_type.h
+++ b/src/observer/common/type/integer_type.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/type/data_type.h"
 
+namespace oceanbase {
+
 /**
  * @brief 整型类型
  * @ingroup DataType
@@ -45,4 +47,5 @@ class IntegerType : public DataType
   RC set_value_from_str(Value &val, const string &data) const override;
 
   RC to_string(const Value &val, string &result) const override;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/string_t.h b/src/observer/common/type/string_t.h
index bf5cf78e4..3d5f3004c 100644
--- a/src/observer/common/type/string_t.h
+++ b/src/observer/common/type/string_t.h
@@ -14,6 +14,9 @@ See the Mulan PSL v2 for more details. */
 #include <cstring>
 
 using namespace std;
+
+namespace oceanbase {
+
 struct string_t
 {
 public:
@@ -101,4 +104,5 @@ struct string_t
     } pointer;
     Inlined inlined;
   } value;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/type/vector_type.h b/src/observer/common/type/vector_type.h
index 9e9f81509..ac1304d29 100644
--- a/src/observer/common/type/vector_type.h
+++ b/src/observer/common/type/vector_type.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/type/data_type.h"
 
+namespace oceanbase {
+
 /**
  * @brief 向量类型
  * @ingroup DataType
@@ -29,4 +31,5 @@ class VectorType : public DataType
   RC multiply(const Value &left, const Value &right, Value &result) const override { return RC::UNIMPLEMENTED; }
 
   RC to_string(const Value &val, string &result) const override { return RC::UNIMPLEMENTED; }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/types.h b/src/observer/common/types.h
index 9c40b7976..d9fd945e9 100644
--- a/src/observer/common/types.h
+++ b/src/observer/common/types.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include <inttypes.h>
 #include <stdint.h>
 
+namespace oceanbase {
+
 /// 磁盘文件，包括存放数据的文件和索引(B+-Tree)文件，都按照页来组织
 /// 每一页都有一个编号，称为PageNum
 using PageNum = int32_t;
@@ -75,3 +77,4 @@ enum class ExecutionMode
 
 /// page的CRC校验和
 using CheckSum = unsigned int;
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/value.cpp b/src/observer/common/value.cpp
index 424c67350..dd2621e23 100644
--- a/src/observer/common/value.cpp
+++ b/src/observer/common/value.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 Value::Value(int val) { set_int(val); }
 
 Value::Value(float val) { set_float(val); }
@@ -28,8 +30,7 @@ Value::Value(bool val) { set_boolean(val); }
 
 Value::Value(const char *s, int len /*= 0*/) { set_string(s, len); }
 
-Value::Value(const string_t& s) { set_string(s.data(), s.size()); }
-
+Value::Value(const string_t &s) { set_string(s.data(), s.size()); }
 
 Value::Value(const Value &other)
 {
@@ -183,12 +184,11 @@ void Value::set_empty_string(int len)
   reset();
   attr_type_ = AttrType::CHARS;
 
-  own_data_ = true;
+  own_data_             = true;
   value_.pointer_value_ = new char[len + 1];
   length_               = len;
   memset(value_.pointer_value_, 0, len);
   value_.pointer_value_[len] = '\0';
-  
 }
 
 void Value::set_value(const Value &value)
@@ -245,7 +245,10 @@ string Value::to_string() const
   return res;
 }
 
-int Value::compare(const Value &other) const { return DataType::type_instance(this->attr_type_)->compare(*this, other); }
+int Value::compare(const Value &other) const
+{
+  return DataType::type_instance(this->attr_type_)->compare(*this, other);
+}
 
 int Value::get_int() const
 {
@@ -349,3 +352,4 @@ bool Value::get_boolean() const
   }
   return false;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/common/value.h b/src/observer/common/value.h
index ca31eedc4..9aeb45a0f 100644
--- a/src/observer/common/value.h
+++ b/src/observer/common/value.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/type/data_type.h"
 #include "common/type/string_t.h"
 
+namespace oceanbase {
+
 /**
  * @brief 属性的值
  * @ingroup DataType
@@ -135,3 +137,4 @@ class Value final
   /// 是否申请并占有内存, 目前对于 CHARS 类型 own_data_ 为true, 其余类型 own_data_ 为false
   bool own_data_ = false;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/session_event.cpp b/src/observer/event/session_event.cpp
index 41ca80d4f..7874070b9 100644
--- a/src/observer/event/session_event.cpp
+++ b/src/observer/event/session_event.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "session_event.h"
 #include "net/communicator.h"
 
+namespace oceanbase {
+
 SessionEvent::SessionEvent(Communicator *comm) : communicator_(comm), sql_result_(communicator_->session()) {}
 
 SessionEvent::~SessionEvent() {}
@@ -22,3 +24,4 @@ SessionEvent::~SessionEvent() {}
 Communicator *SessionEvent::get_communicator() const { return communicator_; }
 
 Session *SessionEvent::session() const { return communicator_->session(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/session_event.h b/src/observer/event/session_event.h
index 7a279ca36..e76744406 100644
--- a/src/observer/event/session_event.h
+++ b/src/observer/event/session_event.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "event/sql_debug.h"
 #include "sql/executor/sql_result.h"
 
+namespace oceanbase {
+
 class Session;
 class Communicator;
 
@@ -46,3 +48,4 @@ class SessionEvent
   SqlDebug      sql_debug_;               ///< SQL调试信息
   string        query_;                   ///< SQL语句
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/sql_debug.cpp b/src/observer/event/sql_debug.cpp
index ab68dc17e..910499bdc 100644
--- a/src/observer/event/sql_debug.cpp
+++ b/src/observer/event/sql_debug.cpp
@@ -18,6 +18,7 @@ See the Mulan PSL v2 for more details. */
 #include "event/sql_debug.h"
 #include "session/session.h"
 
+namespace oceanbase {
 
 void SqlDebug::add_debug_info(const string &debug_info) { debug_infos_.push_back(debug_info); }
 
@@ -52,3 +53,4 @@ void sql_debug(const char *fmt, ...)
 
   delete[] str;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/sql_debug.h b/src/observer/event/sql_debug.h
index 66d182466..fc09487bb 100644
--- a/src/observer/event/sql_debug.h
+++ b/src/observer/event/sql_debug.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "common/lang/list.h"
 
+namespace oceanbase {
+
 /**
  * @brief SQL调试信息
  * @details
@@ -46,3 +48,4 @@ class SqlDebug
  * 在普通文本场景下，调试信息会直接输出到客户端，并增加 '#' 作为前缀。
  */
 void sql_debug(const char *fmt, ...);
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/sql_event.cpp b/src/observer/event/sql_event.cpp
index 6df5fc255..6a310c03f 100644
--- a/src/observer/event/sql_event.cpp
+++ b/src/observer/event/sql_event.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "event/session_event.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 SQLStageEvent::SQLStageEvent(SessionEvent *event, const string &sql) : session_event_(event), sql_(sql) {}
 
 SQLStageEvent::~SQLStageEvent() noexcept
@@ -30,3 +32,4 @@ SQLStageEvent::~SQLStageEvent() noexcept
     stmt_ = nullptr;
   }
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/sql_event.h b/src/observer/event/sql_event.h
index cd7db0659..99c85dc57 100644
--- a/src/observer/event/sql_event.h
+++ b/src/observer/event/sql_event.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/memory.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class SessionEvent;
 class Stmt;
 class ParsedSqlNode;
@@ -51,3 +53,4 @@ class SQLStageEvent
   Stmt                        *stmt_ = nullptr;  ///< Resolver之后生成的数据结构
   unique_ptr<PhysicalOperator> operator_;        ///< 生成的执行计划，也可能没有
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/event/storage_event.h b/src/observer/event/storage_event.h
index 567aca7e1..1570dac22 100644
--- a/src/observer/event/storage_event.h
+++ b/src/observer/event/storage_event.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/seda/stage_event.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 class StorageEvent : public common::StageEvent
@@ -30,3 +32,4 @@ class StorageEvent : public common::StageEvent
 private:
   SQLStageEvent *sql_event_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/main.cpp b/src/observer/main.cpp
index 09c9d0029..f699b737e 100644
--- a/src/observer/main.cpp
+++ b/src/observer/main.cpp
@@ -33,6 +33,8 @@ using namespace common;
 
 #define NET "NET"
 
+namespace oceanbase {
+
 static Server *g_server = nullptr;
 
 void usage()
@@ -207,3 +209,5 @@ int main(int argc, char **argv)
   delete g_server;
   return 0;
 }
+
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/buffered_writer.cpp b/src/observer/net/buffered_writer.cpp
index 58d189372..e2678cbd0 100644
--- a/src/observer/net/buffered_writer.cpp
+++ b/src/observer/net/buffered_writer.cpp
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "net/buffered_writer.h"
 
+namespace oceanbase {
+
 BufferedWriter::BufferedWriter(int fd) : fd_(fd), buffer_() {}
 
 BufferedWriter::BufferedWriter(int fd, int32_t size) : fd_(fd), buffer_(size) {}
@@ -129,3 +131,4 @@ RC BufferedWriter::flush_internal(int32_t size)
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/buffered_writer.h b/src/observer/net/buffered_writer.h
index 3f7d8fc43..04c5a8c3e 100644
--- a/src/observer/net/buffered_writer.h
+++ b/src/observer/net/buffered_writer.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "net/ring_buffer.h"
 
+namespace oceanbase {
+
 /**
  * @brief 支持以缓存模式写入数据到文件/socket
  * @details 缓存使用ring buffer实现，当缓存满时会自动刷新缓存。
@@ -69,4 +71,5 @@ class BufferedWriter
 private:
   int        fd_ = -1;
   RingBuffer buffer_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/cli_communicator.cpp b/src/observer/net/cli_communicator.cpp
index 0e949d900..001bf85c2 100644
--- a/src/observer/net/cli_communicator.cpp
+++ b/src/observer/net/cli_communicator.cpp
@@ -27,6 +27,8 @@ using common::MiniobLineReader;
 
 const std::string LINE_HISTORY_FILE = "./.miniob.history";
 
+namespace oceanbase {
+
 RC CliCommunicator::init(int fd, unique_ptr<Session> session, const string &addr)
 {
   RC rc = PlainCommunicator::init(fd, std::move(session), addr);
@@ -85,3 +87,4 @@ RC CliCommunicator::write_result(SessionEvent *event, bool &need_disconnect)
 }
 
 CliCommunicator::~CliCommunicator() { LOG_INFO("Command history saved to %s", LINE_HISTORY_FILE.c_str()); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/cli_communicator.h b/src/observer/net/cli_communicator.h
index f255ffc6b..1aa518d47 100644
--- a/src/observer/net/cli_communicator.h
+++ b/src/observer/net/cli_communicator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "net/plain_communicator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 用于命令行模式的通讯器
  * @ingroup Communicator
@@ -39,3 +41,4 @@ class CliCommunicator : public PlainCommunicator
 
   int write_fd_ = -1;  ///< 与使用远程通讯模式不同，如果读数据使用标准输入，那么输出应该是标准输出
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/communicator.cpp b/src/observer/net/communicator.cpp
index 7f80d805e..1c9ce1545 100644
--- a/src/observer/net/communicator.cpp
+++ b/src/observer/net/communicator.cpp
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/lang/mutex.h"
 
+namespace oceanbase {
+
 RC Communicator::init(int fd, unique_ptr<Session> session, const string &addr)
 {
   fd_      = fd;
@@ -62,3 +64,4 @@ Communicator *CommunicatorFactory::create(CommunicateProtocol protocol)
     }
   }
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/communicator.h b/src/observer/net/communicator.h
index 0d47300cb..ad631cfb8 100644
--- a/src/observer/net/communicator.h
+++ b/src/observer/net/communicator.h
@@ -23,6 +23,8 @@ class SessionEvent;
 class Session;
 class BufferedWriter;
 
+namespace oceanbase {
+
 /**
  * @defgroup Communicator
  * @brief 负责处理与客户端的通讯
@@ -106,3 +108,4 @@ class CommunicatorFactory
 public:
   Communicator *create(CommunicateProtocol protocol);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/java_thread_pool_thread_handler.cpp b/src/observer/net/java_thread_pool_thread_handler.cpp
index 476fa916e..9d801233e 100644
--- a/src/observer/net/java_thread_pool_thread_handler.cpp
+++ b/src/observer/net/java_thread_pool_thread_handler.cpp
@@ -21,17 +21,19 @@ See the Mulan PSL v2 for more details. */
 #include "common/thread/runnable.h"
 #include "common/queue/simple_queue.h"
 
+namespace oceanbase {
+
 using namespace common;
 
 /**
  * @brief libevent 消息回调函数的参数
- * 
+ *
  */
 struct EventCallbackAg
 {
-  JavaThreadPoolThreadHandler *host = nullptr;
-  Communicator *communicator = nullptr;
-  struct event *ev = nullptr;
+  JavaThreadPoolThreadHandler *host         = nullptr;
+  Communicator                *communicator = nullptr;
+  struct event                *ev           = nullptr;
 };
 
 JavaThreadPoolThreadHandler::~JavaThreadPoolThreadHandler()
@@ -59,10 +61,10 @@ RC JavaThreadPoolThreadHandler::start()
   // 创建线程池
   // 这里写死了线程池的大小，实际上可以从配置文件中读取
   int ret = executor_.init("SQL",  // name
-                            2,     // core size
-                            8,     // max size
-                            60*1000 // keep alive time
-                            );
+      2,                           // core size
+      8,                           // max size
+      60 * 1000                    // keep alive time
+  );
   if (0 != ret) {
     LOG_ERROR("failed to init thread pool executor");
     return RC::INTERNAL;
@@ -71,7 +73,7 @@ RC JavaThreadPoolThreadHandler::start()
   // libevent 的监测消息循环主体，要放在一个线程中执行
   // event_loop_thread 是运行libevent 消息监测循环的函数，会长期运行，并且会放到线程池中占据一个线程
   auto event_worker = std::bind(&JavaThreadPoolThreadHandler::event_loop_thread, this);
-  ret = executor_.execute(event_worker);
+  ret               = executor_.execute(event_worker);
   if (0 != ret) {
     LOG_ERROR("failed to execute event worker");
     return RC::INTERNAL;
@@ -94,7 +96,7 @@ static void event_callback(evutil_socket_t fd, short event, void *arg)
 {
   if (event & (EV_READ | EV_CLOSED)) {
     LOG_TRACE("got event. fd=%d, event=%d", fd, event);
-    EventCallbackAg *ag = (EventCallbackAg *)arg;
+    EventCallbackAg             *ag      = (EventCallbackAg *)arg;
     JavaThreadPoolThreadHandler *handler = ag->host;
     handler->handle_event(ag);
   } else {
@@ -113,7 +115,7 @@ void JavaThreadPoolThreadHandler::handle_event(EventCallbackAg *ag)
 
   // sql_handler 是一个回调函数
   auto sql_handler = [this, ag]() {
-    RC rc = sql_task_handler_.handle_event(ag->communicator); // 这里会有接收消息、处理请求然后返回结果一条龙服务
+    RC rc = sql_task_handler_.handle_event(ag->communicator);  // 这里会有接收消息、处理请求然后返回结果一条龙服务
     if (RC::SUCCESS != rc) {
       LOG_WARN("failed to handle sql task. rc=%s", strrc(rc));
       this->close_connection(ag->communicator);
@@ -128,7 +130,7 @@ void JavaThreadPoolThreadHandler::handle_event(EventCallbackAg *ag)
       // LOG_TRACE("add event. fd=%d, communicator=%p", event_get_fd(ag->ev), this);
     }
   };
-  
+
   executor_.execute(sql_handler);
 }
 
@@ -148,9 +150,9 @@ RC JavaThreadPoolThreadHandler::new_connection(Communicator *communicator)
   int fd = communicator->fd();
   LOG_INFO("new connection. fd=%d", fd);
   EventCallbackAg *ag = new EventCallbackAg;
-  ag->host = this;
-  ag->communicator = communicator;
-  ag->ev = nullptr;
+  ag->host            = this;
+  ag->communicator    = communicator;
+  ag->ev              = nullptr;
   /// 创建一个libevent事件对象。其中EV_READ表示可读事件，就是客户端发消息时会触发事件。
   /// EV_ET 表示边缘触发，有消息时只会触发一次，不会重复触发。这个标识在Linux平台上是支持的，但是有些平台不支持。
   /// 使用EV_ET边缘触发时需要注意一个问题，就是每次一定要把客户端发来的消息都读取完，直到read返回EAGAIN为止。
@@ -185,7 +187,7 @@ RC JavaThreadPoolThreadHandler::close_connection(Communicator *communicator)
 
   {
     lock_guard guard(lock_);
-    auto iter = event_map_.find(communicator);
+    auto       iter = event_map_.find(communicator);
     if (iter == event_map_.end()) {
       LOG_ERROR("cannot find event for communicator %p", communicator);
       return RC::INTERNAL;
@@ -196,8 +198,8 @@ RC JavaThreadPoolThreadHandler::close_connection(Communicator *communicator)
   }
 
   if (ag->ev) {
-    event_del(ag->ev);  // 把当前事件从event_base中删除
-    event_free(ag->ev); // 释放event对象
+    event_del(ag->ev);   // 把当前事件从event_base中删除
+    event_free(ag->ev);  // 释放event对象
     ag->ev = nullptr;
   }
   delete ag;
@@ -245,3 +247,4 @@ RC JavaThreadPoolThreadHandler::await_stop()
   LOG_INFO("end to await event base stopped");
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/java_thread_pool_thread_handler.h b/src/observer/net/java_thread_pool_thread_handler.h
index 98f68dbb9..ebff4c0ce 100644
--- a/src/observer/net/java_thread_pool_thread_handler.h
+++ b/src/observer/net/java_thread_pool_thread_handler.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/thread/thread_pool_executor.h"
 #include "common/lang/mutex.h"
 
+namespace oceanbase {
+
 struct EventCallbackAg;
 
 /**
@@ -67,4 +69,5 @@ class JavaThreadPoolThreadHandler : public ThreadHandler
   map<Communicator *, EventCallbackAg *> event_map_;             /// 每个连接与它关联的数据
 
   SqlTaskHandler sql_task_handler_;  /// SQL请求处理器
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/mysql_communicator.cpp b/src/observer/net/mysql_communicator.cpp
index d543f3a52..bad1d3c83 100644
--- a/src/observer/net/mysql_communicator.cpp
+++ b/src/observer/net/mysql_communicator.cpp
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "net/mysql_communicator.h"
 #include "sql/operator/string_list_physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief MySQL协议相关实现
  * @defgroup MySQLProtocol
@@ -348,7 +350,7 @@ struct HandshakeV10 : public BasePacket
 
     char *buf = net_packet.data();
     int   pos = 0;
-    pos += 3; // skip packet length
+    pos += 3;  // skip packet length
 
     pos += store_int1(buf + pos, packet_header.sequence_id);
     pos += store_int1(buf + pos, protocol);
@@ -379,12 +381,12 @@ struct HandshakeV10 : public BasePacket
  */
 struct OkPacket : public BasePacket
 {
-  int8_t      header         = 0;  // 0x00 for ok and 0xFE for EOF
-  int32_t     affected_rows  = 0;
-  int32_t     last_insert_id = 0;
-  int16_t     status_flags   = 0x22;
-  int16_t     warnings       = 0;
-  string      info;  // human readable status information
+  int8_t  header         = 0;  // 0x00 for ok and 0xFE for EOF
+  int32_t affected_rows  = 0;
+  int32_t last_insert_id = 0;
+  int16_t status_flags   = 0x22;
+  int16_t warnings       = 0;
+  string  info;  // human readable status information
 
   OkPacket(int8_t sequence = 0) : BasePacket(sequence) {}
   virtual ~OkPacket() = default;
@@ -398,7 +400,7 @@ struct OkPacket : public BasePacket
     char *buf = net_packet.data();
     int   pos = 0;
 
-    pos += 3; // skip packet length
+    pos += 3;  // skip packet length
     pos += store_int1(buf + pos, packet_header.sequence_id);
     pos += store_int1(buf + pos, header);
     pos += store_lenenc_int(buf + pos, affected_rows);
@@ -471,11 +473,11 @@ struct EofPacket : public BasePacket
  */
 struct ErrPacket : public BasePacket
 {
-  int8_t      header              = 0xFF;
-  int16_t     error_code          = 0;
-  char        sql_state_marker[1] = {'#'};
-  string sql_state{"HY000"};
-  string error_message;
+  int8_t  header              = 0xFF;
+  int16_t error_code          = 0;
+  char    sql_state_marker[1] = {'#'};
+  string  sql_state{"HY000"};
+  string  error_message;
 
   ErrPacket(int8_t sequence = 0) : BasePacket(sequence) {}
   virtual ~ErrPacket() = default;
@@ -519,7 +521,7 @@ struct QueryPacket
 {
   PacketHeader packet_header;
   int8_t       command;  // 0x03: COM_QUERY
-  string  query;    // the text of the SQL query to execute
+  string       query;    // the text of the SQL query to execute
 };
 
 /**
@@ -695,8 +697,8 @@ RC MysqlCommunicator::write_state(SessionEvent *event, bool &need_disconnect)
 {
   SqlResult *sql_result = event->sql_result();
 
-  const int          buf_size     = 2048;
-  char              *buf          = new char[buf_size];
+  const int     buf_size     = 2048;
+  char         *buf          = new char[buf_size];
   const string &state_string = sql_result->state_string();
   if (state_string.empty()) {
     const char *result = strrc(sql_result->return_code());
@@ -937,16 +939,16 @@ RC MysqlCommunicator::send_column_definition(SqlResult *sql_result, bool &need_d
  * @param no_column_def 为了特殊处理没有返回值的语句，比如insert/delete，需要做特殊处理。
  *                      这种语句只需要返回一个ok packet即可
  */
-RC MysqlCommunicator::send_result_rows(SessionEvent *event, SqlResult *sql_result, bool no_column_def, bool &need_disconnect)
+RC MysqlCommunicator::send_result_rows(
+    SessionEvent *event, SqlResult *sql_result, bool no_column_def, bool &need_disconnect)
 {
   RC rc = RC::SUCCESS;
 
   vector<char> packet;
   packet.resize(4 * 1024 * 1024);  // TODO warning: length cannot be fix
 
-  int    affected_rows = 0;
-  if (event->session()->get_execution_mode() == ExecutionMode::CHUNK_ITERATOR
-      && event->session()->used_chunk_mode()) {
+  int affected_rows = 0;
+  if (event->session()->get_execution_mode() == ExecutionMode::CHUNK_ITERATOR && event->session()->used_chunk_mode()) {
     rc = write_chunk_result(sql_result, packet, affected_rows, need_disconnect);
   } else {
     rc = write_tuple_result(sql_result, packet, affected_rows, need_disconnect);
@@ -971,10 +973,11 @@ RC MysqlCommunicator::send_result_rows(SessionEvent *event, SqlResult *sql_resul
   return rc;
 }
 
-RC MysqlCommunicator::write_tuple_result(SqlResult *sql_result, vector<char> &packet, int &affected_rows, bool &need_disconnect)
+RC MysqlCommunicator::write_tuple_result(
+    SqlResult *sql_result, vector<char> &packet, int &affected_rows, bool &need_disconnect)
 {
-  Tuple *tuple         = nullptr;
-  RC rc = RC::SUCCESS;
+  Tuple *tuple = nullptr;
+  RC     rc    = RC::SUCCESS;
   while (RC::SUCCESS == (rc = sql_result->next_tuple(tuple))) {
     assert(tuple != nullptr);
 
@@ -1016,10 +1019,11 @@ RC MysqlCommunicator::write_tuple_result(SqlResult *sql_result, vector<char> &pa
   }
   return rc;
 }
-RC MysqlCommunicator::write_chunk_result(SqlResult *sql_result, vector<char> &packet, int &affected_rows, bool &need_disconnect)
+RC MysqlCommunicator::write_chunk_result(
+    SqlResult *sql_result, vector<char> &packet, int &affected_rows, bool &need_disconnect)
 {
   Chunk chunk;
-  RC rc = RC::SUCCESS;
+  RC    rc = RC::SUCCESS;
   while (RC::SUCCESS == (rc = sql_result->next_chunk(chunk))) {
     int column_num = chunk.column_num();
     if (column_num == 0) {
@@ -1053,3 +1057,4 @@ RC MysqlCommunicator::write_chunk_result(SqlResult *sql_result, vector<char> &pa
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/mysql_communicator.h b/src/observer/net/mysql_communicator.h
index 2f69794c0..3c27a4668 100644
--- a/src/observer/net/mysql_communicator.h
+++ b/src/observer/net/mysql_communicator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "net/communicator.h"
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 class SqlResult;
 class BasePacket;
 
@@ -105,3 +107,4 @@ class MysqlCommunicator : public Communicator
   //! 这个sequence id是递增的
   int8_t sequence_id_ = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/one_thread_per_connection_thread_handler.cpp b/src/observer/net/one_thread_per_connection_thread_handler.cpp
index ae977f337..75801248c 100644
--- a/src/observer/net/one_thread_per_connection_thread_handler.cpp
+++ b/src/observer/net/one_thread_per_connection_thread_handler.cpp
@@ -25,12 +25,12 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 class Worker
 {
 public:
-  Worker(ThreadHandler &host, Communicator *communicator) 
-    : host_(host), communicator_(communicator)
-  {}
+  Worker(ThreadHandler &host, Communicator *communicator) : host_(host), communicator_(communicator) {}
   ~Worker()
   {
     if (thread_ != nullptr) {
@@ -55,7 +55,7 @@ class Worker
   {
     if (thread_) {
       if (thread_->get_id() == this_thread::get_id()) {
-        thread_->detach(); // 如果当前线程join当前线程，就会卡死
+        thread_->detach();  // 如果当前线程join当前线程，就会卡死
       } else {
         thread_->join();
       }
@@ -74,8 +74,8 @@ class Worker
     }
 
     struct pollfd poll_fd;
-    poll_fd.fd = communicator_->fd();
-    poll_fd.events = POLLIN;
+    poll_fd.fd      = communicator_->fd();
+    poll_fd.events  = POLLIN;
     poll_fd.revents = 0;
 
     while (running_) {
@@ -101,15 +101,15 @@ class Worker
     }
 
     LOG_INFO("worker thread stop. communicator = %p", communicator_);
-    host_.close_connection(communicator_); /// 连接关闭后，当前对象会被删除
+    host_.close_connection(communicator_);  /// 连接关闭后，当前对象会被删除
   }
 
 private:
   ThreadHandler &host_;
   SqlTaskHandler task_handler_;
-  Communicator *communicator_ = nullptr;
-  thread *thread_ = nullptr;
-  volatile bool running_ = true;
+  Communicator  *communicator_ = nullptr;
+  thread        *thread_       = nullptr;
+  volatile bool  running_      = true;
 };
 
 OneThreadPerConnectionThreadHandler::~OneThreadPerConnectionThreadHandler()
@@ -128,7 +128,7 @@ RC OneThreadPerConnectionThreadHandler::new_connection(Communicator *communicato
     return RC::FILE_EXIST;
   }
 
-  Worker *worker = new Worker(*this, communicator);
+  Worker *worker            = new Worker(*this, communicator);
   thread_map_[communicator] = worker;
   return worker->start();
 }
@@ -174,3 +174,4 @@ RC OneThreadPerConnectionThreadHandler::await_stop()
   LOG_INFO("end to await stop one thread per connection thread handler");
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/one_thread_per_connection_thread_handler.h b/src/observer/net/one_thread_per_connection_thread_handler.h
index 12c9f1c4d..44f4b8c64 100644
--- a/src/observer/net/one_thread_per_connection_thread_handler.h
+++ b/src/observer/net/one_thread_per_connection_thread_handler.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/mutex.h"
 #include "common/lang/unordered_map.h"
 
+namespace oceanbase {
+
 class Worker;
 
 /**
@@ -46,4 +48,5 @@ class OneThreadPerConnectionThreadHandler : public ThreadHandler
   unordered_map<Communicator *, Worker *> thread_map_;  // 当前编译器没有支持jthread
   /// 保护线程安全的锁
   mutex lock_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/plain_communicator.cpp b/src/observer/net/plain_communicator.cpp
index e16746716..462006139 100644
--- a/src/observer/net/plain_communicator.cpp
+++ b/src/observer/net/plain_communicator.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "session/session.h"
 #include "sql/expr/tuple.h"
 
+namespace oceanbase {
+
 PlainCommunicator::PlainCommunicator()
 {
   send_message_delimiter_.assign(1, '\0');
@@ -237,8 +239,7 @@ RC PlainCommunicator::write_result_internal(SessionEvent *event, bool &need_disc
   }
 
   rc = RC::SUCCESS;
-  if (event->session()->get_execution_mode() == ExecutionMode::CHUNK_ITERATOR
-      && event->session()->used_chunk_mode()) {
+  if (event->session()->get_execution_mode() == ExecutionMode::CHUNK_ITERATOR && event->session()->used_chunk_mode()) {
     rc = write_chunk_result(sql_result);
   } else {
     rc = write_tuple_result(sql_result);
@@ -272,7 +273,7 @@ RC PlainCommunicator::write_result_internal(SessionEvent *event, bool &need_disc
 
 RC PlainCommunicator::write_tuple_result(SqlResult *sql_result)
 {
-  RC rc = RC::SUCCESS;
+  RC     rc    = RC::SUCCESS;
   Tuple *tuple = nullptr;
   while (RC::SUCCESS == (rc = sql_result->next_tuple(tuple))) {
     assert(tuple != nullptr);
@@ -326,7 +327,7 @@ RC PlainCommunicator::write_tuple_result(SqlResult *sql_result)
 
 RC PlainCommunicator::write_chunk_result(SqlResult *sql_result)
 {
-  RC rc = RC::SUCCESS;
+  RC    rc = RC::SUCCESS;
   Chunk chunk;
   while (RC::SUCCESS == (rc = sql_result->next_chunk(chunk))) {
     int col_num = chunk.column_num();
@@ -370,4 +371,5 @@ RC PlainCommunicator::write_chunk_result(SqlResult *sql_result)
     rc = RC::SUCCESS;
   }
   return rc;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/plain_communicator.h b/src/observer/net/plain_communicator.h
index 0dfabf9a2..ed6f5e606 100644
--- a/src/observer/net/plain_communicator.h
+++ b/src/observer/net/plain_communicator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "net/communicator.h"
 #include "common/lang/vector.h"
 
+namespace oceanbase {
+
 class SqlResult;
 
 /**
@@ -44,3 +46,4 @@ class PlainCommunicator : public Communicator
   vector<char> send_message_delimiter_;  ///< 发送消息分隔符
   vector<char> debug_message_prefix_;    ///< 调试信息前缀
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/ring_buffer.cpp b/src/observer/net/ring_buffer.cpp
index c3b5f74e0..a5b35c218 100644
--- a/src/observer/net/ring_buffer.cpp
+++ b/src/observer/net/ring_buffer.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "net/ring_buffer.h"
 
+namespace oceanbase {
+
 const int32_t DEFAULT_BUFFER_SIZE = 16 * 1024;
 
 RingBuffer::RingBuffer() : RingBuffer(DEFAULT_BUFFER_SIZE) {}
@@ -32,7 +34,7 @@ RC RingBuffer::read(char *buf, int32_t size, int32_t &read_size)
 
   RC rc     = RC::SUCCESS;
   read_size = 0;
-  while (OB_SUCC(rc) && read_size<size &&this->size()> 0) {
+  while (OB_SUCC(rc) && read_size < size && this->size() > 0) {
     const char *tmp_buf  = nullptr;
     int32_t     tmp_size = 0;
     rc                   = buffer(tmp_buf, tmp_size);
@@ -90,7 +92,7 @@ RC RingBuffer::write(const char *data, int32_t size, int32_t &write_size)
 
   RC rc      = RC::SUCCESS;
   write_size = 0;
-  while (OB_SUCC(rc) && write_size<size &&this->remain()> 0) {
+  while (OB_SUCC(rc) && write_size < size && this->remain() > 0) {
 
     const int32_t read_pos     = this->read_pos();
     const int32_t tmp_buf_size = (read_pos <= write_pos_) ? (capacity() - write_pos_) : (read_pos - write_pos_);
@@ -104,3 +106,4 @@ RC RingBuffer::write(const char *data, int32_t size, int32_t &write_size)
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/ring_buffer.h b/src/observer/net/ring_buffer.h
index 39f241a09..96b1a0304 100644
--- a/src/observer/net/ring_buffer.h
+++ b/src/observer/net/ring_buffer.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/lang/vector.h"
 
+namespace oceanbase {
+
 /**
  * @brief 环形缓存，当前用于通讯写入数据时的缓存
  * @ingroup Communicator
@@ -93,3 +95,4 @@ class RingBuffer
   int32_t      data_size_ = 0;  ///< 已经写入的数据量
   int32_t      write_pos_ = 0;  ///< 当前写指针的位置，范围不会超出[0, capacity)
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/server.cpp b/src/observer/net/server.cpp
index 53724e2c1..32980b323 100644
--- a/src/observer/net/server.cpp
+++ b/src/observer/net/server.cpp
@@ -42,6 +42,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 ServerParam::ServerParam()
 {
   listen_addr        = INADDR_ANY;
@@ -344,3 +346,4 @@ void CliServer::shutdown()
   // cleanup
   started_ = false;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/server.h b/src/observer/net/server.h
index 2e39cb0ab..f14e5dc47 100644
--- a/src/observer/net/server.h
+++ b/src/observer/net/server.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "net/server_param.h"
 
+namespace oceanbase {
+
 class Communicator;
 class ThreadHandler;
 
@@ -97,4 +99,5 @@ class CliServer : public Server
 
 private:
   volatile bool started_ = false;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/server_param.h b/src/observer/net/server_param.h
index 2a498a79a..b5aa503b7 100644
--- a/src/observer/net/server_param.h
+++ b/src/observer/net/server_param.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "net/communicator.h"
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 /**
  * @brief 服务端启动参数
  * @ingroup Communicator
@@ -49,3 +51,4 @@ class ServerParam
 
   string thread_handling;  ///< 线程池模型
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/sql_task_handler.cpp b/src/observer/net/sql_task_handler.cpp
index 90f0609b4..66ca60dfa 100644
--- a/src/observer/net/sql_task_handler.cpp
+++ b/src/observer/net/sql_task_handler.cpp
@@ -18,10 +18,12 @@ See the Mulan PSL v2 for more details. */
 #include "event/sql_event.h"
 #include "session/session.h"
 
+namespace oceanbase {
+
 RC SqlTaskHandler::handle_event(Communicator *communicator)
 {
   SessionEvent *event = nullptr;
-  RC rc = communicator->read_event(event);
+  RC            rc    = communicator->read_event(event);
   if (OB_FAIL(rc)) {
     return rc;
   }
@@ -88,4 +90,5 @@ RC SqlTaskHandler::handle_sql(SQLStageEvent *sql_event)
   }
 
   return rc;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/sql_task_handler.h b/src/observer/net/sql_task_handler.h
index 8c1294ee7..4197c3020 100644
--- a/src/observer/net/sql_task_handler.h
+++ b/src/observer/net/sql_task_handler.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/parser/resolve_stage.h"
 #include "sql/query_cache/query_cache_stage.h"
 
+namespace oceanbase {
+
 class Communicator;
 class SQLStageEvent;
 
@@ -50,6 +52,7 @@ class SqlTaskHandler
   QueryCacheStage query_cache_stage_;  /// 查询缓存阶段
   ParseStage      parse_stage_;        /// 解析阶段。将SQL解析成语法树 ParsedSqlNode
   ResolveStage    resolve_stage_;      /// 解析阶段。将语法树解析成Stmt(statement)
-  OptimizeStage optimize_stage_;  /// 优化阶段。将语句优化成执行计划，包含规则优化和物理优化
-  ExecuteStage  execute_stage_;   /// 执行阶段
+  OptimizeStage optimize_stage_;     /// 优化阶段。将语句优化成执行计划，包含规则优化和物理优化
+  ExecuteStage    execute_stage_;      /// 执行阶段
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/thread_handler.cpp b/src/observer/net/thread_handler.cpp
index 941fcdfd9..7e4c31b11 100644
--- a/src/observer/net/thread_handler.cpp
+++ b/src/observer/net/thread_handler.cpp
@@ -20,7 +20,9 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "common/lang/string.h"
 
-ThreadHandler * ThreadHandler::create(const char *name)
+namespace oceanbase {
+
+ThreadHandler *ThreadHandler::create(const char *name)
 {
   const char *default_name = "one-thread-per-connection";
   if (nullptr == name || common::is_blank(name)) {
@@ -35,4 +37,5 @@ ThreadHandler * ThreadHandler::create(const char *name)
     LOG_ERROR("unknown thread handler: %s", name);
     return nullptr;
   }
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/net/thread_handler.h b/src/observer/net/thread_handler.h
index fd876e63d..5d6ac2ab6 100644
--- a/src/observer/net/thread_handler.h
+++ b/src/observer/net/thread_handler.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class Communicator;
 
 /**
@@ -63,3 +65,4 @@ class ThreadHandler
    */
   static ThreadHandler *create(const char *name);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/session/session.cpp b/src/observer/session/session.cpp
index a5d3297e6..c11e4e384 100644
--- a/src/observer/session/session.cpp
+++ b/src/observer/session/session.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/default/default_handler.h"
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 Session &Session::default_session()
 {
   static Session session;
@@ -77,12 +79,12 @@ Trx *Session::current_trx()
 }
 
 void Session::destroy_trx()
-  {
-    if (trx_ != nullptr) {
-      db_->trx_kit().destroy_trx(trx_);
-      trx_ = nullptr;
-    }
+{
+  if (trx_ != nullptr) {
+    db_->trx_kit().destroy_trx(trx_);
+    trx_ = nullptr;
   }
+}
 
 thread_local Session *thread_session = nullptr;
 
@@ -93,3 +95,4 @@ Session *Session::current_session() { return thread_session; }
 void Session::set_current_request(SessionEvent *request) { current_request_ = request; }
 
 SessionEvent *Session::current_request() const { return current_request_; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/session/session.h b/src/observer/session/session.h
index e9139eda3..61dabc147 100644
--- a/src/observer/session/session.h
+++ b/src/observer/session/session.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/types.h"
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 class Trx;
 class Db;
 class SessionEvent;
@@ -124,3 +126,4 @@ class Session
 
   ExecutionMode execution_mode_ = ExecutionMode::TUPLE_ITERATOR;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/session/session_stage.cpp b/src/observer/session/session_stage.cpp
index eed271357..44955f321 100644
--- a/src/observer/session/session_stage.cpp
+++ b/src/observer/session/session_stage.cpp
@@ -28,6 +28,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 // Destructor
 SessionStage::~SessionStage() {}
 
@@ -111,3 +113,4 @@ RC SessionStage::handle_sql(SQLStageEvent *sql_event)
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/session/session_stage.h b/src/observer/session/session_stage.h
index 2762c66ca..86322b5d3 100644
--- a/src/observer/session/session_stage.h
+++ b/src/observer/session/session_stage.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/parser/resolve_stage.h"
 #include "sql/query_cache/query_cache_stage.h"
 
+namespace oceanbase {
+
 /**
  * @brief SEDA处理的stage
  * @defgroup SQLStage
@@ -56,3 +58,4 @@ class SessionStage
   OptimizeStage   optimize_stage_;
   ExecuteStage    execute_stage_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/session/thread_data.cpp b/src/observer/session/thread_data.cpp
index 96a3d963b..782f45b73 100644
--- a/src/observer/session/thread_data.cpp
+++ b/src/observer/session/thread_data.cpp
@@ -15,6 +15,9 @@ See the Mulan PSL v2 for more details. */
 #include "session/thread_data.h"
 #include "session/session.h"
 
+namespace oceanbase {
+
 thread_local ThreadData *ThreadData::thread_data_;
 
-Trx *ThreadData::trx() const { return (session_ == nullptr) ? nullptr : session_->current_trx(); }
\ No newline at end of file
+Trx *ThreadData::trx() const { return (session_ == nullptr) ? nullptr : session_->current_trx(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/session/thread_data.h b/src/observer/session/thread_data.h
index 698c4b1a5..8ee9d1669 100644
--- a/src/observer/session/thread_data.h
+++ b/src/observer/session/thread_data.h
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 class Trx;
 class Session;
 
@@ -37,4 +39,5 @@ class ThreadData
 
 private:
   Session *session_ = nullptr;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/analyze_table_executor.cpp b/src/observer/sql/executor/analyze_table_executor.cpp
index cb724da98..7542bd1ca 100644
--- a/src/observer/sql/executor/analyze_table_executor.cpp
+++ b/src/observer/sql/executor/analyze_table_executor.cpp
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC AnalyzeTableExecutor::execute(SQLStageEvent *sql_event)
 {
   RC            rc            = RC::SUCCESS;
@@ -33,8 +35,8 @@ RC AnalyzeTableExecutor::execute(SQLStageEvent *sql_event)
       static_cast<int>(stmt->type()));
 
   AnalyzeTableStmt *analyze_table_stmt = static_cast<AnalyzeTableStmt *>(stmt);
-  SqlResult     *sql_result      = session_event->sql_result();
-  const char    *table_name      = analyze_table_stmt->table_name().c_str();
+  SqlResult        *sql_result         = session_event->sql_result();
+  const char       *table_name         = analyze_table_stmt->table_name().c_str();
 
   Db    *db    = session->get_current_db();
   Table *table = db->find_table(table_name);
@@ -44,7 +46,7 @@ RC AnalyzeTableExecutor::execute(SQLStageEvent *sql_event)
     int table_id = table->table_id();
     table->get_record_scanner(scanner_, session->current_trx(), ReadWriteMode::READ_ONLY);
     Record dummy;
-    int row_nums = 0;
+    int    row_nums = 0;
     while (OB_SUCC(rc = scanner_->next(dummy))) {
       row_nums++;
     }
@@ -53,7 +55,7 @@ RC AnalyzeTableExecutor::execute(SQLStageEvent *sql_event)
     } else {
       return rc;
     }
-  
+
     TableStats stats(row_nums);
     Catalog::get_instance().update_table_stats(table_id, stats);
   } else {
@@ -63,10 +65,11 @@ RC AnalyzeTableExecutor::execute(SQLStageEvent *sql_event)
   return rc;
 }
 
-AnalyzeTableExecutor::~AnalyzeTableExecutor() 
+AnalyzeTableExecutor::~AnalyzeTableExecutor()
 {
   if (scanner_ != nullptr) {
     delete scanner_;
     scanner_ = nullptr;
   }
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/analyze_table_executor.h b/src/observer/sql/executor/analyze_table_executor.h
index 15e8f58b5..52919162a 100644
--- a/src/observer/sql/executor/analyze_table_executor.h
+++ b/src/observer/sql/executor/analyze_table_executor.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 class RecordScanner;
 
@@ -30,3 +32,4 @@ class AnalyzeTableExecutor
 private:
   RecordScanner *scanner_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/command_executor.cpp b/src/observer/sql/executor/command_executor.cpp
index de9527afe..c56c6283c 100644
--- a/src/observer/sql/executor/command_executor.cpp
+++ b/src/observer/sql/executor/command_executor.cpp
@@ -27,6 +27,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/executor/trx_end_executor.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 RC CommandExecutor::execute(SQLStageEvent *sql_event)
 {
   Stmt *stmt = sql_event->stmt();
@@ -102,3 +104,4 @@ RC CommandExecutor::execute(SQLStageEvent *sql_event)
 
   return rc;
 }
+}  // namespace oceanbase
diff --git a/src/observer/sql/executor/command_executor.h b/src/observer/sql/executor/command_executor.h
index d0114c4c1..b60b083c1 100644
--- a/src/observer/sql/executor/command_executor.h
+++ b/src/observer/sql/executor/command_executor.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -35,3 +37,4 @@ class CommandExecutor
 
   RC execute(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/create_index_executor.cpp b/src/observer/sql/executor/create_index_executor.cpp
index 6c99dda0b..5ca70e475 100644
--- a/src/observer/sql/executor/create_index_executor.cpp
+++ b/src/observer/sql/executor/create_index_executor.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/create_index_stmt.h"
 #include "storage/table/table.h"
 
+namespace oceanbase {
+
 RC CreateIndexExecutor::execute(SQLStageEvent *sql_event)
 {
   Stmt    *stmt    = sql_event->stmt();
@@ -33,4 +35,5 @@ RC CreateIndexExecutor::execute(SQLStageEvent *sql_event)
   Trx   *trx   = session->current_trx();
   Table *table = create_index_stmt->table();
   return table->create_index(trx, create_index_stmt->field_meta(), create_index_stmt->index_name().c_str());
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/create_index_executor.h b/src/observer/sql/executor/create_index_executor.h
index 6a7c54896..f101ff22a 100644
--- a/src/observer/sql/executor/create_index_executor.h
+++ b/src/observer/sql/executor/create_index_executor.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -31,3 +33,4 @@ class CreateIndexExecutor
 
   RC execute(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/create_table_executor.cpp b/src/observer/sql/executor/create_table_executor.cpp
index d01d8da76..dac941754 100644
--- a/src/observer/sql/executor/create_table_executor.cpp
+++ b/src/observer/sql/executor/create_table_executor.cpp
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/create_table_stmt.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
+
 RC CreateTableExecutor::execute(SQLStageEvent *sql_event)
 {
   Stmt    *stmt    = sql_event->stmt();
@@ -32,7 +34,11 @@ RC CreateTableExecutor::execute(SQLStageEvent *sql_event)
   CreateTableStmt *create_table_stmt = static_cast<CreateTableStmt *>(stmt);
 
   const char *table_name = create_table_stmt->table_name().c_str();
-  RC rc = session->get_current_db()->create_table(table_name, create_table_stmt->attr_infos(), create_table_stmt->primary_keys(), create_table_stmt->storage_format());
+  RC          rc         = session->get_current_db()->create_table(table_name,
+      create_table_stmt->attr_infos(),
+      create_table_stmt->primary_keys(),
+      create_table_stmt->storage_format());
 
   return rc;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/create_table_executor.h b/src/observer/sql/executor/create_table_executor.h
index 3a7ace584..bc9dff4a3 100644
--- a/src/observer/sql/executor/create_table_executor.h
+++ b/src/observer/sql/executor/create_table_executor.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -30,3 +32,4 @@ class CreateTableExecutor
 
   RC execute(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/desc_table_executor.cpp b/src/observer/sql/executor/desc_table_executor.cpp
index ea993fa51..589b73d83 100644
--- a/src/observer/sql/executor/desc_table_executor.cpp
+++ b/src/observer/sql/executor/desc_table_executor.cpp
@@ -25,6 +25,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC DescTableExecutor::execute(SQLStageEvent *sql_event)
 {
   RC            rc            = RC::SUCCESS;
@@ -64,3 +66,4 @@ RC DescTableExecutor::execute(SQLStageEvent *sql_event)
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/desc_table_executor.h b/src/observer/sql/executor/desc_table_executor.h
index 7e6a40951..93905fc90 100644
--- a/src/observer/sql/executor/desc_table_executor.h
+++ b/src/observer/sql/executor/desc_table_executor.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -30,3 +32,4 @@ class DescTableExecutor
 
   RC execute(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/execute_stage.cpp b/src/observer/sql/executor/execute_stage.cpp
index f4354b32f..66c6fd651 100644
--- a/src/observer/sql/executor/execute_stage.cpp
+++ b/src/observer/sql/executor/execute_stage.cpp
@@ -25,6 +25,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC ExecuteStage::handle_request(SQLStageEvent *sql_event)
 {
   RC rc = RC::SUCCESS;
@@ -58,3 +60,4 @@ RC ExecuteStage::handle_request_with_physical_operator(SQLStageEvent *sql_event)
   sql_result->set_operator(std::move(physical_operator));
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/execute_stage.h b/src/observer/sql/executor/execute_stage.h
index 5eca68161..f9c00b57c 100644
--- a/src/observer/sql/executor/execute_stage.h
+++ b/src/observer/sql/executor/execute_stage.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 class SessionEvent;
 class SelectStmt;
@@ -32,3 +34,4 @@ class ExecuteStage
   RC handle_request(SQLStageEvent *event);
   RC handle_request_with_physical_operator(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/help_executor.h b/src/observer/sql/executor/help_executor.h
index c5946aa9b..4865b949a 100644
--- a/src/observer/sql/executor/help_executor.h
+++ b/src/observer/sql/executor/help_executor.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/executor/sql_result.h"
 #include "sql/operator/string_list_physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief Help语句执行器
  * @ingroup Executor
@@ -57,3 +59,4 @@ class HelpExecutor
     return RC::SUCCESS;
   }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/load_data_executor.cpp b/src/observer/sql/executor/load_data_executor.cpp
index f841a8474..f6b7b9169 100644
--- a/src/observer/sql/executor/load_data_executor.cpp
+++ b/src/observer/sql/executor/load_data_executor.cpp
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC LoadDataExecutor::execute(SQLStageEvent *sql_event)
 {
   RC            rc         = RC::SUCCESS;
@@ -81,9 +83,9 @@ RC insert_record_from_file(
   return rc;
 }
 
-
 // TODO: pax format and row format
-void LoadDataExecutor::load_data(Table *table, const char *file_name, char terminated, char enclosed, SqlResult *sql_result)
+void LoadDataExecutor::load_data(
+    Table *table, const char *file_name, char terminated, char enclosed, SqlResult *sql_result)
 {
   // your code here
   stringstream result_string;
@@ -102,13 +104,13 @@ void LoadDataExecutor::load_data(Table *table, const char *file_name, char termi
   const int sys_field_num = table->table_meta().sys_field_num();
   const int field_num     = table->table_meta().field_num() - sys_field_num;
 
-  vector<Value>       record_values(field_num);
-  string              line;
+  vector<Value>  record_values(field_num);
+  string         line;
   vector<string> file_values;
-  const string        delim("|");
-  int                      line_num        = 0;
-  int                      insertion_count = 0;
-  RC                       rc              = RC::SUCCESS;
+  const string   delim("|");
+  int            line_num        = 0;
+  int            insertion_count = 0;
+  RC             rc              = RC::SUCCESS;
   while (!fs.eof() && RC::SUCCESS == rc) {
     getline(fs, line);
     line_num++;
@@ -147,3 +149,4 @@ void LoadDataExecutor::load_data(Table *table, const char *file_name, char termi
   LOG_INFO("load data done. row num: %s, result: %s", insertion_count, strrc(rc));
   sql_result->set_return_code(RC::SUCCESS);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/load_data_executor.h b/src/observer/sql/executor/load_data_executor.h
index 42f54d7dc..b6c721952 100644
--- a/src/observer/sql/executor/load_data_executor.h
+++ b/src/observer/sql/executor/load_data_executor.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 class Table;
 class SqlResult;
@@ -35,3 +37,4 @@ class LoadDataExecutor
 private:
   void load_data(Table *table, const char *file_name, char terminated, char enclosed, SqlResult *sql_result);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/set_variable_executor.cpp b/src/observer/sql/executor/set_variable_executor.cpp
index 28b4a9df8..8fadd35a8 100644
--- a/src/observer/sql/executor/set_variable_executor.cpp
+++ b/src/observer/sql/executor/set_variable_executor.cpp
@@ -10,105 +10,108 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/executor/set_variable_executor.h"
 
+namespace oceanbase {
+
 RC SetVariableExecutor::execute(SQLStageEvent *sql_event)
 {
-    RC rc = RC::SUCCESS;
-
-    Session         *session = sql_event->session_event()->session();
-    SetVariableStmt *stmt    = (SetVariableStmt *)sql_event->stmt();
-
-    const char  *var_name  = stmt->var_name();
-    const Value &var_value = stmt->var_value();
-    // TODO: refactor the variable configuration
-    if (strcasecmp(var_name, "sql_debug") == 0) {
-      bool bool_value = false;
-      rc              = var_value_to_boolean(var_value, bool_value);
-      if (rc == RC::SUCCESS) {
-        session->set_sql_debug(bool_value);
-        LOG_TRACE("set sql_debug to %d", bool_value);
-      }
-    } else if (strcasecmp(var_name, "execution_mode") == 0) {
-      ExecutionMode  execution_mode = ExecutionMode::UNKNOWN_MODE;
-      rc = get_execution_mode(var_value, execution_mode);
-      if (rc == RC::SUCCESS && execution_mode != ExecutionMode::UNKNOWN_MODE) {
-        session->set_execution_mode(execution_mode);
-      } else {
-        rc = RC::INVALID_ARGUMENT;
-      }
-    } else if (strcasecmp(var_name, "hash_join") == 0) { // TODO: remove this configuration
-        bool bool_value = false;
-        rc              = var_value_to_boolean(var_value, bool_value);
-        if (rc == RC::SUCCESS) {
-          session->set_hash_join(bool_value);
-          LOG_TRACE("set hash_join to %d", bool_value);
-        }
-      } else if (strcasecmp(var_name, "use_cascade") == 0) {
-        // TODO: remove this params, due to the dblab needed, likely to be long-existing
-        bool bool_value = false;
-        rc              = var_value_to_boolean(var_value, bool_value);
-        if (rc == RC::SUCCESS) {
-          session->set_use_cascade(bool_value);
-          LOG_TRACE("set use_cascade to %d", bool_value);
-        }
-      } else {
-      rc = RC::VARIABLE_NOT_EXISTS;
+  RC rc = RC::SUCCESS;
+
+  Session         *session = sql_event->session_event()->session();
+  SetVariableStmt *stmt    = (SetVariableStmt *)sql_event->stmt();
+
+  const char  *var_name  = stmt->var_name();
+  const Value &var_value = stmt->var_value();
+  // TODO: refactor the variable configuration
+  if (strcasecmp(var_name, "sql_debug") == 0) {
+    bool bool_value = false;
+    rc              = var_value_to_boolean(var_value, bool_value);
+    if (rc == RC::SUCCESS) {
+      session->set_sql_debug(bool_value);
+      LOG_TRACE("set sql_debug to %d", bool_value);
+    }
+  } else if (strcasecmp(var_name, "execution_mode") == 0) {
+    ExecutionMode execution_mode = ExecutionMode::UNKNOWN_MODE;
+    rc                           = get_execution_mode(var_value, execution_mode);
+    if (rc == RC::SUCCESS && execution_mode != ExecutionMode::UNKNOWN_MODE) {
+      session->set_execution_mode(execution_mode);
+    } else {
+      rc = RC::INVALID_ARGUMENT;
     }
+  } else if (strcasecmp(var_name, "hash_join") == 0) {  // TODO: remove this configuration
+    bool bool_value = false;
+    rc              = var_value_to_boolean(var_value, bool_value);
+    if (rc == RC::SUCCESS) {
+      session->set_hash_join(bool_value);
+      LOG_TRACE("set hash_join to %d", bool_value);
+    }
+  } else if (strcasecmp(var_name, "use_cascade") == 0) {
+    // TODO: remove this params, due to the dblab needed, likely to be long-existing
+    bool bool_value = false;
+    rc              = var_value_to_boolean(var_value, bool_value);
+    if (rc == RC::SUCCESS) {
+      session->set_use_cascade(bool_value);
+      LOG_TRACE("set use_cascade to %d", bool_value);
+    }
+  } else {
+    rc = RC::VARIABLE_NOT_EXISTS;
+  }
 
-    return rc;
+  return rc;
 }
 
 RC SetVariableExecutor::var_value_to_boolean(const Value &var_value, bool &bool_value) const
 {
-    RC rc = RC::SUCCESS;
+  RC rc = RC::SUCCESS;
 
-    if (var_value.attr_type() == AttrType::BOOLEANS) {
-      bool_value = var_value.get_boolean();
-    } else if (var_value.attr_type() == AttrType::INTS) {
-      bool_value = var_value.get_int() != 0;
-    } else if (var_value.attr_type() == AttrType::FLOATS) {
-      bool_value = var_value.get_float() != 0.0;
-    } else if (var_value.attr_type() == AttrType::CHARS) {
+  if (var_value.attr_type() == AttrType::BOOLEANS) {
+    bool_value = var_value.get_boolean();
+  } else if (var_value.attr_type() == AttrType::INTS) {
+    bool_value = var_value.get_int() != 0;
+  } else if (var_value.attr_type() == AttrType::FLOATS) {
+    bool_value = var_value.get_float() != 0.0;
+  } else if (var_value.attr_type() == AttrType::CHARS) {
 
-      string true_strings[] = {"true", "on", "yes", "t", "1"};
+    string true_strings[] = {"true", "on", "yes", "t", "1"};
 
-      string false_strings[] = {"false", "off", "no", "f", "0"};
+    string false_strings[] = {"false", "off", "no", "f", "0"};
 
-      for (size_t i = 0; i < sizeof(true_strings) / sizeof(true_strings[0]); i++) {
-        if (strcasecmp(var_value.get_string().c_str(), true_strings[i].c_str()) == 0) {
-          bool_value = true;
-          return rc;
-        }
+    for (size_t i = 0; i < sizeof(true_strings) / sizeof(true_strings[0]); i++) {
+      if (strcasecmp(var_value.get_string().c_str(), true_strings[i].c_str()) == 0) {
+        bool_value = true;
+        return rc;
       }
+    }
 
-      for (size_t i = 0; i < sizeof(false_strings) / sizeof(false_strings[0]); i++) {
-        if (strcasecmp(var_value.get_string().c_str(), false_strings[i].c_str()) == 0) {
-          bool_value = false;
-          return rc;
-        }
+    for (size_t i = 0; i < sizeof(false_strings) / sizeof(false_strings[0]); i++) {
+      if (strcasecmp(var_value.get_string().c_str(), false_strings[i].c_str()) == 0) {
+        bool_value = false;
+        return rc;
       }
-      rc = RC::VARIABLE_NOT_VALID;
     }
+    rc = RC::VARIABLE_NOT_VALID;
+  }
 
-    return rc;
+  return rc;
 }
 
 RC SetVariableExecutor::get_execution_mode(const Value &var_value, ExecutionMode &execution_mode) const
 {
-    RC rc = RC::SUCCESS;
-  
-    if (var_value.attr_type() == AttrType::CHARS) {
-      if (strcasecmp(var_value.get_string().c_str(), "TUPLE_ITERATOR") == 0) {
-        execution_mode = ExecutionMode::TUPLE_ITERATOR;
-      } else if (strcasecmp(var_value.get_string().c_str(), "CHUNK_ITERATOR") == 0) {
-        execution_mode = ExecutionMode::CHUNK_ITERATOR;
-      } else {
-        execution_mode = ExecutionMode::UNKNOWN_MODE;
-        rc = RC::VARIABLE_NOT_VALID;
-      }
-    } else  {
+  RC rc = RC::SUCCESS;
+
+  if (var_value.attr_type() == AttrType::CHARS) {
+    if (strcasecmp(var_value.get_string().c_str(), "TUPLE_ITERATOR") == 0) {
+      execution_mode = ExecutionMode::TUPLE_ITERATOR;
+    } else if (strcasecmp(var_value.get_string().c_str(), "CHUNK_ITERATOR") == 0) {
+      execution_mode = ExecutionMode::CHUNK_ITERATOR;
+    } else {
       execution_mode = ExecutionMode::UNKNOWN_MODE;
-      rc = RC::VARIABLE_NOT_VALID;
+      rc             = RC::VARIABLE_NOT_VALID;
     }
+  } else {
+    execution_mode = ExecutionMode::UNKNOWN_MODE;
+    rc             = RC::VARIABLE_NOT_VALID;
+  }
 
-    return rc;
+  return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/set_variable_executor.h b/src/observer/sql/executor/set_variable_executor.h
index 55e45f757..91c28ec42 100644
--- a/src/observer/sql/executor/set_variable_executor.h
+++ b/src/observer/sql/executor/set_variable_executor.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "session/session.h"
 #include "sql/stmt/set_variable_stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief SetVariable语句执行器
  * @ingroup Executor
@@ -37,3 +39,4 @@ class SetVariableExecutor
 
   RC get_execution_mode(const Value &var_value, ExecutionMode &execution_mode) const;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/show_tables_executor.h b/src/observer/sql/executor/show_tables_executor.h
index 0b6acf6ca..c1de1774c 100644
--- a/src/observer/sql/executor/show_tables_executor.h
+++ b/src/observer/sql/executor/show_tables_executor.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/string_list_physical_operator.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
+
 /**
  * @brief 显示所有表的执行器
  * @ingroup Executor
@@ -56,3 +58,4 @@ class ShowTablesExecutor
     return RC::SUCCESS;
   }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/sql_result.cpp b/src/observer/sql/executor/sql_result.cpp
index 7207679a8..2dd21c0aa 100644
--- a/src/observer/sql/executor/sql_result.cpp
+++ b/src/observer/sql/executor/sql_result.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "session/session.h"
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 SqlResult::SqlResult(Session *session) : session_(session) {}
 
 void SqlResult::set_tuple_schema(const TupleSchema &schema) { tuple_schema_ = schema; }
@@ -82,3 +84,4 @@ void SqlResult::set_operator(unique_ptr<PhysicalOperator> oper)
   operator_ = std::move(oper);
   operator_->tuple_schema(tuple_schema_);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/sql_result.h b/src/observer/sql/executor/sql_result.h
index e3ac999d5..9a1bc001a 100644
--- a/src/observer/sql/executor/sql_result.h
+++ b/src/observer/sql/executor/sql_result.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/tuple.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class Session;
 
 /**
@@ -57,3 +59,4 @@ class SqlResult
   RC                           return_code_ = RC::SUCCESS;
   string                       state_string_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/trx_begin_executor.h b/src/observer/sql/executor/trx_begin_executor.h
index 87f3d2d88..beb403774 100644
--- a/src/observer/sql/executor/trx_begin_executor.h
+++ b/src/observer/sql/executor/trx_begin_executor.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "session/session.h"
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 /**
  * @brief 事务开始语句的执行器
  * @ingroup Executor
@@ -42,3 +44,4 @@ class TrxBeginExecutor
     return trx->start_if_need();
   }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/executor/trx_end_executor.h b/src/observer/sql/executor/trx_end_executor.h
index aa149f8c3..258e88958 100644
--- a/src/observer/sql/executor/trx_end_executor.h
+++ b/src/observer/sql/executor/trx_end_executor.h
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/stmt.h"
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 /**
  * @brief 事务结束的执行器，可以是提交或回滚
  * @ingroup Executor
@@ -50,3 +52,4 @@ class TrxEndExecutor
     return rc;
   }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/aggregate_hash_table.cpp b/src/observer/sql/expr/aggregate_hash_table.cpp
index 46aaaf993..2d8becacb 100644
--- a/src/observer/sql/expr/aggregate_hash_table.cpp
+++ b/src/observer/sql/expr/aggregate_hash_table.cpp
@@ -13,15 +13,17 @@ See the Mulan PSL v2 for more details. */
 
 // ----------------------------------StandardAggregateHashTable------------------
 
+namespace oceanbase {
+
 RC StandardAggregateHashTable::add_chunk(Chunk &groups_chunk, Chunk &aggrs_chunk)
 {
-    if (groups_chunk.rows() != aggrs_chunk.rows()) {
+  if (groups_chunk.rows() != aggrs_chunk.rows()) {
     LOG_WARN("groups_chunk and aggrs_chunk have different rows: %d, %d", groups_chunk.rows(), aggrs_chunk.rows());
     return RC::INVALID_ARGUMENT;
   }
   for (int i = 0; i < groups_chunk.rows(); i++) {
-    vector<Value> group_by_values;
-    vector<void*> aggr_values;
+    vector<Value>  group_by_values;
+    vector<void *> aggr_values;
 
     for (int j = 0; j < groups_chunk.column_num(); j++) {
       group_by_values.emplace_back(groups_chunk.get_value(j, i));
@@ -30,18 +32,19 @@ RC StandardAggregateHashTable::add_chunk(Chunk &groups_chunk, Chunk &aggrs_chunk
     auto it = aggr_values_.find(group_by_values);
     if (it == aggr_values_.end()) {
       for (size_t j = 0; j < aggr_types_.size(); j++) {
-        void * state_ptr = create_aggregate_state(aggr_types_[j], aggr_child_types_[j]);
+        void *state_ptr = create_aggregate_state(aggr_types_[j], aggr_child_types_[j]);
         if (state_ptr == nullptr) {
           LOG_WARN("create aggregate state failed");
           return RC::INTERNAL;
-        }   
+        }
         aggr_values.emplace_back(state_ptr);
       }
       aggr_values_.emplace(group_by_values, aggr_values);
     }
     auto &aggr = aggr_values_.find(group_by_values)->second;
     for (size_t aggr_idx = 0; aggr_idx < aggr.size(); aggr_idx++) {
-      RC rc = aggregate_state_update_by_value(aggr[aggr_idx], aggr_types_[aggr_idx], aggr_child_types_[aggr_idx], aggrs_chunk.get_value(aggr_idx, i));
+      RC rc = aggregate_state_update_by_value(
+          aggr[aggr_idx], aggr_types_[aggr_idx], aggr_child_types_[aggr_idx], aggrs_chunk.get_value(aggr_idx, i));
       if (rc != RC::SUCCESS) {
         LOG_WARN("update aggregate state failed");
         return rc;
@@ -70,8 +73,10 @@ RC StandardAggregateHashTable::Scanner::next(Chunk &output_chunk)
       auto col_idx = output_chunk.column_ids(i);
       if (col_idx >= static_cast<int>(group_by_values.size())) {
         int aggr_real_idx = col_idx - group_by_values.size();
-        rc = finialize_aggregate_state(aggrs[aggr_real_idx], hash_table_->aggr_types_[aggr_real_idx],
-                                       hash_table_->aggr_child_types_[aggr_real_idx], output_chunk.column(i));
+        rc                = finialize_aggregate_state(aggrs[aggr_real_idx],
+            hash_table_->aggr_types_[aggr_real_idx],
+            hash_table_->aggr_child_types_[aggr_real_idx],
+            output_chunk.column(i));
         if (rc != RC::SUCCESS) {
           LOG_WARN("finialize aggregate state failed");
           return rc;
@@ -265,16 +270,18 @@ void LinearProbingAggregateHashTable<V>::add_batch(int *input_keys, V *input_val
   // off 全部初始化为 0
 
   // for (; i + SIMD_WIDTH <= len;) {
-    // 1: 根据 `inv` 变量的值，从 `input_keys` 中 `selective load` `SIMD_WIDTH` 个不同的输入键值对。
-    // 2. 计算 i += |inv|, `|inv|` 表示 `inv` 中有效的个数 
-    // 3. 计算 hash 值，
-    // 4. 根据聚合类型（目前只支持 sum），在哈希表中更新聚合结果。如果本次循环，没有找到key[i] 在哈希表中的位置，则不更新聚合结果。
-    // 5. gather 操作，根据 hash 值将 keys_ 的 gather 结果写入 table_key 中。
-    // 6. 更新 inv 和 off。如果本次循环key[i] 聚合完成，则inv[i]=-1，表示该位置在下次循环中读取新的键值对。
-    // 如果本次循环 key[i] 未在哈希表中聚合完成（table_key[i] != key[i]），则inv[i] = 0，表示该位置在下次循环中不需要读取新的键值对。
-    // 如果本次循环中，key[i]聚合完成，则off[i] 更新为 0，表示线性探测偏移量为 0，key[i] 未完成聚合，则off[i]++,表示线性探测偏移量加 1。
+  // 1: 根据 `inv` 变量的值，从 `input_keys` 中 `selective load` `SIMD_WIDTH` 个不同的输入键值对。
+  // 2. 计算 i += |inv|, `|inv|` 表示 `inv` 中有效的个数
+  // 3. 计算 hash 值，
+  // 4. 根据聚合类型（目前只支持 sum），在哈希表中更新聚合结果。如果本次循环，没有找到key[i]
+  // 在哈希表中的位置，则不更新聚合结果。
+  // 5. gather 操作，根据 hash 值将 keys_ 的 gather 结果写入 table_key 中。
+  // 6. 更新 inv 和 off。如果本次循环key[i] 聚合完成，则inv[i]=-1，表示该位置在下次循环中读取新的键值对。
+  // 如果本次循环 key[i] 未在哈希表中聚合完成（table_key[i] != key[i]），则inv[i] =
+  // 0，表示该位置在下次循环中不需要读取新的键值对。 如果本次循环中，key[i]聚合完成，则off[i] 更新为
+  // 0，表示线性探测偏移量为 0，key[i] 未完成聚合，则off[i]++,表示线性探测偏移量加 1。
   // }
-  //7. 通过标量线性探测，处理剩余键值对
+  // 7. 通过标量线性探测，处理剩余键值对
 
   // resize_if_need();
 }
@@ -287,3 +294,4 @@ const int LinearProbingAggregateHashTable<V>::DEFAULT_CAPACITY = 16384;
 template class LinearProbingAggregateHashTable<int>;
 template class LinearProbingAggregateHashTable<float>;
 #endif
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/aggregate_hash_table.h b/src/observer/sql/expr/aggregate_hash_table.h
index 8b47d390f..a77054ee5 100644
--- a/src/observer/sql/expr/aggregate_hash_table.h
+++ b/src/observer/sql/expr/aggregate_hash_table.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "sql/expr/expression.h"
 
+namespace oceanbase {
+
 /**
  * @brief 用于hash group by 的哈希表实现，不支持并发访问。
  */
@@ -176,3 +178,4 @@ class LinearProbingAggregateHashTable : public AggregateHashTable
   AggregateExpr::Type aggregate_type_;
 };
 #endif  // USE_SIMD
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/aggregate_state.cpp b/src/observer/sql/expr/aggregate_state.cpp
index 78db6e0c9..5e49e7cfe 100644
--- a/src/observer/sql/expr/aggregate_state.cpp
+++ b/src/observer/sql/expr/aggregate_state.cpp
@@ -14,6 +14,9 @@ See the Mulan PSL v2 for more details. */
 #ifdef USE_SIMD
 #include "common/math/simd_util.h"
 #endif
+
+namespace oceanbase {
+
 template <typename T>
 void SumState<T>::update(const T *values, int size)
 {
@@ -25,7 +28,7 @@ void SumState<T>::update(const T *values, int size)
   }
 #else
   for (int i = 0; i < size; ++i) {
- 	  value += values[i];
+    value += values[i];
   }
 #endif
 }
@@ -34,7 +37,7 @@ template <typename T>
 void AvgState<T>::update(const T *values, int size)
 {
   for (int i = 0; i < size; ++i) {
- 	  value += values[i];
+    value += values[i];
   }
   count += size;
 }
@@ -45,9 +48,9 @@ void CountState<T>::update(const T *values, int size)
   value += size;
 }
 
-void* create_aggregate_state(AggregateExpr::Type aggr_type, AttrType attr_type)
+void *create_aggregate_state(AggregateExpr::Type aggr_type, AttrType attr_type)
 {
-  void* state_ptr = nullptr;
+  void *state_ptr = nullptr;
   if (aggr_type == AggregateExpr::Type::SUM) {
     if (attr_type == AttrType::INTS) {
       state_ptr = malloc(sizeof(SumState<int>));
@@ -77,25 +80,25 @@ void* create_aggregate_state(AggregateExpr::Type aggr_type, AttrType attr_type)
   return state_ptr;
 }
 
-RC aggregate_state_update_by_value(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, const Value& val)
+RC aggregate_state_update_by_value(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, const Value &val)
 {
   RC rc = RC::SUCCESS;
   if (aggr_type == AggregateExpr::Type::SUM) {
     if (attr_type == AttrType::INTS) {
-      static_cast<SumState<int>*>(state)->update(val.get_int());
+      static_cast<SumState<int> *>(state)->update(val.get_int());
     } else if (attr_type == AttrType::FLOATS) {
-      static_cast<SumState<float>*>(state)->update(val.get_float());
+      static_cast<SumState<float> *>(state)->update(val.get_float());
     } else {
       LOG_WARN("unsupported aggregate value type");
       return RC::UNIMPLEMENTED;
     }
   } else if (aggr_type == AggregateExpr::Type::COUNT) {
-    static_cast<CountState<int>*>(state)->update(1);
+    static_cast<CountState<int> *>(state)->update(1);
   } else if (aggr_type == AggregateExpr::Type::AVG) {
     if (attr_type == AttrType::INTS) {
-      static_cast<AvgState<int>*>(state)->update(val.get_int());
+      static_cast<AvgState<int> *>(state)->update(val.get_int());
     } else if (attr_type == AttrType::FLOATS) {
-      static_cast<AvgState<float>*>(state)->update(val.get_float());
+      static_cast<AvgState<float> *>(state)->update(val.get_float());
     } else {
       LOG_WARN("unsupported aggregate value type");
       return RC::UNIMPLEMENTED;
@@ -111,14 +114,14 @@ template <class STATE, typename T>
 void append_to_column(void *state, Column &column)
 {
   STATE *state_ptr = reinterpret_cast<STATE *>(state);
-  T res = state_ptr->template finalize<T>();
+  T      res       = state_ptr->template finalize<T>();
   column.append_one((char *)&res);
 }
 
-RC finialize_aggregate_state(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column& col)
+RC finialize_aggregate_state(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column &col)
 {
   RC rc = RC::SUCCESS;
-  if ( aggr_type == AggregateExpr::Type::SUM) {
+  if (aggr_type == AggregateExpr::Type::SUM) {
     if (attr_type == AttrType::INTS) {
       append_to_column<SumState<int>, int>(state, col);
     } else if (attr_type == AttrType::FLOATS) {
@@ -137,7 +140,7 @@ RC finialize_aggregate_state(void *state, AggregateExpr::Type aggr_type, AttrTyp
     } else {
       rc = RC::UNIMPLEMENTED;
       LOG_WARN("unsupported aggregate value type");
-    }// 
+    }  //
   } else {
     rc = RC::UNIMPLEMENTED;
     LOG_WARN("unsupported aggregator type");
@@ -149,11 +152,11 @@ template <class STATE, typename T>
 void update_aggregate_state(void *state, const Column &column)
 {
   STATE *state_ptr = reinterpret_cast<STATE *>(state);
-  T *    data      = (T *)column.data();
+  T     *data      = (T *)column.data();
   state_ptr->update(data, column.count());
 }
 
-RC aggregate_state_update_by_column(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column& col)
+RC aggregate_state_update_by_column(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column &col)
 {
   RC rc = RC::SUCCESS;
   if (aggr_type == AggregateExpr::Type::SUM) {
@@ -190,3 +193,4 @@ template class CountState<int>;
 
 template class AvgState<int>;
 template class AvgState<float>;
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/aggregate_state.h b/src/observer/sql/expr/aggregate_state.h
index 6a9835ead..3e2b63a0d 100644
--- a/src/observer/sql/expr/aggregate_state.h
+++ b/src/observer/sql/expr/aggregate_state.h
@@ -10,6 +10,9 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/expr/expression.h"
 #include "common/type/attr_type.h"
+
+namespace oceanbase {
+
 template <class T>
 class SumState
 {
@@ -65,4 +68,5 @@ void *create_aggregate_state(AggregateExpr::Type aggr_type, AttrType attr_type);
 RC aggregate_state_update_by_value(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, const Value &val);
 RC aggregate_state_update_by_column(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column &col);
 
-RC finialize_aggregate_state(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column &col);
\ No newline at end of file
+RC finialize_aggregate_state(void *state, AggregateExpr::Type aggr_type, AttrType attr_type, Column &col);
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/aggregator.cpp b/src/observer/sql/expr/aggregator.cpp
index 29ba468a7..1a6446b18 100644
--- a/src/observer/sql/expr/aggregator.cpp
+++ b/src/observer/sql/expr/aggregator.cpp
@@ -15,22 +15,25 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/aggregator.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 RC SumAggregator::accumulate(const Value &value)
 {
   if (value_.attr_type() == AttrType::UNDEFINED) {
     value_ = value;
     return RC::SUCCESS;
   }
-  
+
   ASSERT(value.attr_type() == value_.attr_type(), "type mismatch. value type: %s, value_.type: %s", 
         attr_type_to_string(value.attr_type()), attr_type_to_string(value_.attr_type()));
-  
+
   Value::add(value, value_, value_);
   return RC::SUCCESS;
 }
 
-RC SumAggregator::evaluate(Value& result)
+RC SumAggregator::evaluate(Value &result)
 {
   result = value_;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/aggregator.h b/src/observer/sql/expr/aggregator.h
index 08a9b8ae3..f78f89b6e 100644
--- a/src/observer/sql/expr/aggregator.h
+++ b/src/observer/sql/expr/aggregator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class Aggregator
 {
 public:
@@ -35,3 +37,4 @@ class SumAggregator : public Aggregator
   RC accumulate(const Value &value) override;
   RC evaluate(Value &result) override;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/arithmetic_operator.hpp b/src/observer/sql/expr/arithmetic_operator.hpp
index e5560703a..c3191cc27 100644
--- a/src/observer/sql/expr/arithmetic_operator.hpp
+++ b/src/observer/sql/expr/arithmetic_operator.hpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/common/column.h"
 
+namespace oceanbase {
+
 struct Equal
 {
   template <class T>
@@ -372,3 +374,4 @@ void compare_result(T *left, T *right, int n, vector<uint8_t> &result, CompOp op
     default: break;
   }
 }
+}
\ No newline at end of file
diff --git a/src/observer/sql/expr/composite_tuple.cpp b/src/observer/sql/expr/composite_tuple.cpp
index 40ff81284..09d69eda2 100644
--- a/src/observer/sql/expr/composite_tuple.cpp
+++ b/src/observer/sql/expr/composite_tuple.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 int CompositeTuple::cell_num() const
 {
   int num = 0;
@@ -64,8 +66,9 @@ RC CompositeTuple::find_cell(const TupleCellSpec &spec, Value &cell) const
 
 void CompositeTuple::add_tuple(unique_ptr<Tuple> tuple) { tuples_.push_back(std::move(tuple)); }
 
-Tuple &CompositeTuple::tuple_at(size_t index) 
-{ 
+Tuple &CompositeTuple::tuple_at(size_t index)
+{
   ASSERT(index < tuples_.size(), "index=%d, tuples_size=%d", index, tuples_.size());
-  return *tuples_[index]; 
-}
\ No newline at end of file
+  return *tuples_[index];
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/composite_tuple.h b/src/observer/sql/expr/composite_tuple.h
index f8883295d..ffd6b702f 100644
--- a/src/observer/sql/expr/composite_tuple.h
+++ b/src/observer/sql/expr/composite_tuple.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/expr/tuple.h"
 
+namespace oceanbase {
+
 /**
  * @brief 组合的Tuple
  * @ingroup Tuple
@@ -48,3 +50,4 @@ class CompositeTuple : public Tuple
 private:
   vector<unique_ptr<Tuple>> tuples_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/expression.cpp b/src/observer/sql/expr/expression.cpp
index df5d1c807..e0163b160 100644
--- a/src/observer/sql/expr/expression.cpp
+++ b/src/observer/sql/expr/expression.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC FieldExpr::get_value(const Tuple &tuple, Value &value) const
 {
   return tuple.find_cell(TupleCellSpec(table_name(), field_name()), value);
@@ -91,7 +93,7 @@ RC CastExpr::cast(const Value &value, Value &cast_value) const
 RC CastExpr::get_value(const Tuple &tuple, Value &result) const
 {
   Value value;
-  RC rc = child_->get_value(tuple, value);
+  RC    rc = child_->get_value(tuple, value);
   if (rc != RC::SUCCESS) {
     return rc;
   }
@@ -102,7 +104,7 @@ RC CastExpr::get_value(const Tuple &tuple, Value &result) const
 RC CastExpr::get_column(Chunk &chunk, Column &column)
 {
   Column child_column;
-  RC rc = child_->get_column(chunk, child_column);
+  RC     rc = child_->get_column(chunk, child_column);
   if (rc != RC::SUCCESS) {
     return rc;
   }
@@ -122,7 +124,7 @@ RC CastExpr::get_column(Chunk &chunk, Column &column)
 RC CastExpr::try_get_value(Value &result) const
 {
   Value value;
-  RC rc = child_->try_get_value(value);
+  RC    rc = child_->try_get_value(value);
   if (rc != RC::SUCCESS) {
     return rc;
   }
@@ -134,8 +136,7 @@ RC CastExpr::try_get_value(Value &result) const
 
 ComparisonExpr::ComparisonExpr(CompOp comp, unique_ptr<Expression> left, unique_ptr<Expression> right)
     : comp_(comp), left_(std::move(left)), right_(std::move(right))
-{
-}
+{}
 
 ComparisonExpr::~ComparisonExpr() {}
 
@@ -175,8 +176,8 @@ RC ComparisonExpr::compare_value(const Value &left, const Value &right, bool &re
 RC ComparisonExpr::try_get_value(Value &cell) const
 {
   if (left_->type() == ExprType::VALUE && right_->type() == ExprType::VALUE) {
-    ValueExpr *  left_value_expr  = static_cast<ValueExpr *>(left_.get());
-    ValueExpr *  right_value_expr = static_cast<ValueExpr *>(right_.get());
+    ValueExpr   *left_value_expr  = static_cast<ValueExpr *>(left_.get());
+    ValueExpr   *right_value_expr = static_cast<ValueExpr *>(right_.get());
     const Value &left_cell        = left_value_expr->get_value();
     const Value &right_cell       = right_value_expr->get_value();
 
@@ -250,10 +251,10 @@ RC ComparisonExpr::eval(Chunk &chunk, vector<uint8_t> &select)
       rows = left_column.count();
     }
     for (int i = 0; i < rows; ++i) {
-      Value left_val = left_column.get_value(i);
+      Value left_val  = left_column.get_value(i);
       Value right_val = right_column.get_value(i);
-      bool        result   = false;
-      rc                   = compare_value(left_val, right_val, result);
+      bool  result    = false;
+      rc              = compare_value(left_val, right_val, result);
       if (rc != RC::SUCCESS) {
         LOG_WARN("failed to compare tuple cells. rc=%s", strrc(rc));
         return rc;
@@ -346,8 +347,7 @@ AttrType ArithmeticExpr::value_type() const
     return left_->value_type();
   }
 
-  if ((left_->value_type() == AttrType::INTS) &&
-   (right_->value_type() == AttrType::INTS) &&
+  if ((left_->value_type() == AttrType::INTS) && (right_->value_type() == AttrType::INTS) &&
       arithmetic_type_ != Type::DIV) {
     return AttrType::INTS;
   }
@@ -628,3 +628,4 @@ RC AggregateExpr::type_from_string(const char *type_str, AggregateExpr::Type &ty
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/expression.h b/src/observer/sql/expr/expression.h
index 02dc27c2f..2216c1591 100644
--- a/src/observer/sql/expr/expression.h
+++ b/src/observer/sql/expr/expression.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/aggregator.h"
 #include "storage/common/chunk.h"
 
+namespace oceanbase {
+
 class Tuple;
 
 /**
@@ -528,3 +530,4 @@ class AggregateExpr : public Expression
   Type                   aggregate_type_;
   unique_ptr<Expression> child_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/expression_iterator.cpp b/src/observer/sql/expr/expression_iterator.cpp
index ca8cd6d5e..4a98ba2e2 100644
--- a/src/observer/sql/expr/expression_iterator.cpp
+++ b/src/observer/sql/expr/expression_iterator.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC ExpressionIterator::iterate_child_expr(Expression &expr, function<RC(unique_ptr<Expression> &)> callback)
 {
   RC rc = RC::SUCCESS;
@@ -25,13 +27,13 @@ RC ExpressionIterator::iterate_child_expr(Expression &expr, function<RC(unique_p
   switch (expr.type()) {
     case ExprType::CAST: {
       auto &cast_expr = static_cast<CastExpr &>(expr);
-      rc = callback(cast_expr.child());
+      rc              = callback(cast_expr.child());
     } break;
 
     case ExprType::COMPARISON: {
 
       auto &comparison_expr = static_cast<ComparisonExpr &>(expr);
-      rc = callback(comparison_expr.left());
+      rc                    = callback(comparison_expr.left());
 
       if (OB_SUCC(rc)) {
         rc = callback(comparison_expr.right());
@@ -52,7 +54,7 @@ RC ExpressionIterator::iterate_child_expr(Expression &expr, function<RC(unique_p
     case ExprType::ARITHMETIC: {
 
       auto &arithmetic_expr = static_cast<ArithmeticExpr &>(expr);
-      rc = callback(arithmetic_expr.left());
+      rc                    = callback(arithmetic_expr.left());
       if (OB_SUCC(rc)) {
         rc = callback(arithmetic_expr.right());
       }
@@ -60,7 +62,7 @@ RC ExpressionIterator::iterate_child_expr(Expression &expr, function<RC(unique_p
 
     case ExprType::AGGREGATION: {
       auto &aggregate_expr = static_cast<AggregateExpr &>(expr);
-      rc = callback(aggregate_expr.child());
+      rc                   = callback(aggregate_expr.child());
     } break;
 
     case ExprType::NONE:
@@ -77,4 +79,5 @@ RC ExpressionIterator::iterate_child_expr(Expression &expr, function<RC(unique_p
   }
 
   return rc;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/expression_iterator.h b/src/observer/sql/expr/expression_iterator.h
index a03095c19..ecbc355ad 100644
--- a/src/observer/sql/expr/expression_iterator.h
+++ b/src/observer/sql/expr/expression_iterator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/functional.h"
 #include "common/lang/memory.h"
 
+namespace oceanbase {
+
 class Expression;
 
 class ExpressionIterator
@@ -25,3 +27,4 @@ class ExpressionIterator
 public:
   static RC iterate_child_expr(Expression &expr, function<RC(unique_ptr<Expression> &)> callback);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/expression_tuple.h b/src/observer/sql/expr/expression_tuple.h
index c70cd4fc2..96cf78632 100644
--- a/src/observer/sql/expr/expression_tuple.h
+++ b/src/observer/sql/expr/expression_tuple.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 template <typename ExprPointerType>
 class ExpressionTuple : public Tuple
 {
@@ -88,3 +90,4 @@ class ExpressionTuple : public Tuple
   const vector<ExprPointerType> &expressions_;
   const Tuple                   *child_tuple_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/tuple.h b/src/observer/sql/expr/tuple.h
index 053aa9a91..c76aab11f 100644
--- a/src/observer/sql/expr/tuple.h
+++ b/src/observer/sql/expr/tuple.h
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "storage/record/record.h"
 
+namespace oceanbase {
+
 class Table;
 
 /**
@@ -440,3 +442,4 @@ class JoinedTuple : public Tuple
   Tuple *left_  = nullptr;
   Tuple *right_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/tuple_cell.cpp b/src/observer/sql/expr/tuple_cell.cpp
index 4646643dd..419630093 100644
--- a/src/observer/sql/expr/tuple_cell.cpp
+++ b/src/observer/sql/expr/tuple_cell.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 TupleCellSpec::TupleCellSpec(const char *table_name, const char *field_name, const char *alias)
 {
   if (table_name) {
@@ -43,5 +45,5 @@ TupleCellSpec::TupleCellSpec(const char *alias)
   }
 }
 
-TupleCellSpec::TupleCellSpec(const string &alias) : alias_(alias)
-{}
+TupleCellSpec::TupleCellSpec(const string &alias) : alias_(alias) {}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/expr/tuple_cell.h b/src/observer/sql/expr/tuple_cell.h
index 3268f2f29..88172922a 100644
--- a/src/observer/sql/expr/tuple_cell.h
+++ b/src/observer/sql/expr/tuple_cell.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/field/field_meta.h"
 
+namespace oceanbase {
+
 class TupleCellSpec final
 {
 public:
@@ -38,3 +40,4 @@ class TupleCellSpec final
   string field_name_;
   string alias_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/aggregate_vec_physical_operator.cpp b/src/observer/sql/operator/aggregate_vec_physical_operator.cpp
index cace563a4..e20ca8db6 100644
--- a/src/observer/sql/operator/aggregate_vec_physical_operator.cpp
+++ b/src/observer/sql/operator/aggregate_vec_physical_operator.cpp
@@ -17,13 +17,15 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 AggregateVecPhysicalOperator::AggregateVecPhysicalOperator(vector<Expression *> &&expressions)
 {
   aggregate_expressions_ = std::move(expressions);
   value_expressions_.reserve(aggregate_expressions_.size());
 
   ranges::for_each(aggregate_expressions_, [this](Expression *expr) {
-    auto *      aggregate_expr = static_cast<AggregateExpr *>(expr);
+    auto       *aggregate_expr = static_cast<AggregateExpr *>(expr);
     Expression *child_expr     = aggregate_expr->child().get();
     ASSERT(child_expr != nullptr, "aggregation expression must have a child expression");
     value_expressions_.emplace_back(child_expr);
@@ -57,7 +59,8 @@ RC AggregateVecPhysicalOperator::open(Trx *trx)
       value_expressions_[aggr_idx]->get_column(chunk_, column);
       ASSERT(aggregate_expressions_[aggr_idx]->type() == ExprType::AGGREGATION, "expect aggregate expression");
       auto *aggregate_expr = static_cast<AggregateExpr *>(aggregate_expressions_[aggr_idx]);
-      rc = aggregate_state_update_by_column(aggr_values_.at(aggr_idx), aggregate_expr->aggregate_type(), aggregate_expr->child()->value_type(), column);
+      rc                   = aggregate_state_update_by_column(
+          aggr_values_.at(aggr_idx), aggregate_expr->aggregate_type(), aggregate_expr->child()->value_type(), column);
       if (OB_FAIL(rc)) {
         LOG_INFO("failed to update aggregate state. rc=%s", strrc(rc));
         return rc;
@@ -76,7 +79,7 @@ template <class STATE, typename T>
 void AggregateVecPhysicalOperator::update_aggregate_state(void *state, const Column &column)
 {
   STATE *state_ptr = reinterpret_cast<STATE *>(state);
-  T *    data      = (T *)column.data();
+  T     *data      = (T *)column.data();
   state_ptr->update(data, column.count());
 }
 
@@ -89,7 +92,10 @@ RC AggregateVecPhysicalOperator::next(Chunk &chunk)
     auto pos = i;
     ASSERT(aggregate_expressions_[pos]->type() == ExprType::AGGREGATION, "expect aggregation expression");
     auto *aggregate_expr = static_cast<AggregateExpr *>(aggregate_expressions_[pos]);
-    RC rc = finialize_aggregate_state(aggr_values_.at(pos), aggregate_expr->aggregate_type(), aggregate_expr->child()->value_type(), output_chunk_.column(i));
+    RC    rc             = finialize_aggregate_state(aggr_values_.at(pos),
+        aggregate_expr->aggregate_type(),
+        aggregate_expr->child()->value_type(),
+        output_chunk_.column(i));
     if (OB_FAIL(rc)) {
       LOG_INFO("failed to finialize aggregate state. rc=%s", strrc(rc));
       return rc;
@@ -108,3 +114,4 @@ RC AggregateVecPhysicalOperator::close()
   LOG_INFO("close group by operator");
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/aggregate_vec_physical_operator.h b/src/observer/sql/operator/aggregate_vec_physical_operator.h
index 1afab13f2..f7911ce15 100644
--- a/src/observer/sql/operator/aggregate_vec_physical_operator.h
+++ b/src/observer/sql/operator/aggregate_vec_physical_operator.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 聚合物理算子 (Vectorized)
  * @ingroup PhysicalOperator
@@ -66,3 +68,4 @@ class AggregateVecPhysicalOperator : public PhysicalOperator
   AggregateValues      aggr_values_;
   bool                 outputed_ = false;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/calc_logical_operator.h b/src/observer/sql/operator/calc_logical_operator.h
index 985dd388d..caf2ac751 100644
--- a/src/observer/sql/operator/calc_logical_operator.h
+++ b/src/observer/sql/operator/calc_logical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 逻辑算子描述当前执行计划要做什么
  * @details 可以看OptimizeStage中相关的代码
@@ -29,3 +31,4 @@ class CalcLogicalOperator : public LogicalOperator
   LogicalOperatorType type() const override { return LogicalOperatorType::CALC; }
   OpType              get_op_type() const override { return OpType::LOGICALCALCULATE; }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/calc_physical_operator.h b/src/observer/sql/operator/calc_physical_operator.h
index 4b704af80..6d64f0fb8 100644
--- a/src/observer/sql/operator/calc_physical_operator.h
+++ b/src/observer/sql/operator/calc_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/expression_tuple.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class CalcPhysicalOperator : public PhysicalOperator
 {
 public:
@@ -73,3 +75,4 @@ class CalcPhysicalOperator : public PhysicalOperator
   ExpressionTuple<unique_ptr<Expression>> tuple_;
   bool                                    emitted_ = false;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/delete_logical_operator.cpp b/src/observer/sql/operator/delete_logical_operator.cpp
index 5fc03f34e..2952796ba 100644
--- a/src/observer/sql/operator/delete_logical_operator.cpp
+++ b/src/observer/sql/operator/delete_logical_operator.cpp
@@ -14,4 +14,7 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/delete_logical_operator.h"
 
+namespace oceanbase {
+
 DeleteLogicalOperator::DeleteLogicalOperator(Table *table) : table_(table) {}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/delete_logical_operator.h b/src/observer/sql/operator/delete_logical_operator.h
index effc305c9..848a58c6a 100644
--- a/src/observer/sql/operator/delete_logical_operator.h
+++ b/src/observer/sql/operator/delete_logical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 逻辑算子，用于执行delete语句
  * @ingroup LogicalOperator
@@ -33,3 +35,4 @@ class DeleteLogicalOperator : public LogicalOperator
 private:
   Table *table_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/delete_physical_operator.cpp b/src/observer/sql/operator/delete_physical_operator.cpp
index ea239a9b0..fe3d1e715 100644
--- a/src/observer/sql/operator/delete_physical_operator.cpp
+++ b/src/observer/sql/operator/delete_physical_operator.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/table/table.h"
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 RC DeletePhysicalOperator::open(Trx *trx)
 {
   if (children_.empty()) {
@@ -60,12 +62,7 @@ RC DeletePhysicalOperator::open(Trx *trx)
   return RC::SUCCESS;
 }
 
-RC DeletePhysicalOperator::next()
-{
-  return RC::RECORD_EOF;
-}
+RC DeletePhysicalOperator::next() { return RC::RECORD_EOF; }
 
-RC DeletePhysicalOperator::close()
-{
-  return RC::SUCCESS;
-}
+RC DeletePhysicalOperator::close() { return RC::SUCCESS; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/delete_physical_operator.h b/src/observer/sql/operator/delete_physical_operator.h
index 241447985..28d910ffd 100644
--- a/src/observer/sql/operator/delete_physical_operator.h
+++ b/src/observer/sql/operator/delete_physical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class Trx;
 class DeleteStmt;
 
@@ -45,3 +47,4 @@ class DeletePhysicalOperator : public PhysicalOperator
   Trx           *trx_   = nullptr;
   vector<Record> records_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/explain_logical_operator.h b/src/observer/sql/operator/explain_logical_operator.h
index c226f0f9b..2b53e7fc4 100644
--- a/src/observer/sql/operator/explain_logical_operator.h
+++ b/src/observer/sql/operator/explain_logical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief Explain逻辑算子
  * @ingroup LogicalOperator
@@ -30,3 +32,4 @@ class ExplainLogicalOperator : public LogicalOperator
 
   OpType get_op_type() const override { return OpType::LOGICALEXPLAIN; }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/explain_physical_operator.cpp b/src/observer/sql/operator/explain_physical_operator.cpp
index 1ff2933a3..3f565df6c 100644
--- a/src/observer/sql/operator/explain_physical_operator.cpp
+++ b/src/observer/sql/operator/explain_physical_operator.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC ExplainPhysicalOperator::open(Trx *)
 {
   ASSERT(children_.size() == 1, "explain must has 1 child");
@@ -53,12 +55,12 @@ RC ExplainPhysicalOperator::next(Chunk &chunk)
   }
   generate_physical_plan();
 
-  Value         cell(physical_plan_.c_str());
-  auto column = make_unique<Column>();
+  Value cell(physical_plan_.c_str());
+  auto  column = make_unique<Column>();
   column->init(cell, chunk.rows());
   chunk.add_column(std::move(column), 0);
   return RC::SUCCESS;
 }
 
 Tuple *ExplainPhysicalOperator::current_tuple() { return &tuple_; }
-
+}  // namespace oceanbase
diff --git a/src/observer/sql/operator/explain_physical_operator.h b/src/observer/sql/operator/explain_physical_operator.h
index 10c1b6d7a..038850619 100644
--- a/src/observer/sql/operator/explain_physical_operator.h
+++ b/src/observer/sql/operator/explain_physical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief Explain物理算子
  * @ingroup PhysicalOperator
@@ -54,3 +56,4 @@ class ExplainPhysicalOperator : public PhysicalOperator
   string         physical_plan_;
   ValueListTuple tuple_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/expr_vec_physical_operator.cpp b/src/observer/sql/operator/expr_vec_physical_operator.cpp
index 64a3a99bb..dd9c03b0f 100644
--- a/src/observer/sql/operator/expr_vec_physical_operator.cpp
+++ b/src/observer/sql/operator/expr_vec_physical_operator.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 ExprVecPhysicalOperator::ExprVecPhysicalOperator(vector<Expression *> &&expressions)
 {
   expressions_ = std::move(expressions);
@@ -60,3 +62,4 @@ RC ExprVecPhysicalOperator::close()
   LOG_INFO("close group by operator");
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/expr_vec_physical_operator.h b/src/observer/sql/operator/expr_vec_physical_operator.h
index bbd5a9a91..505ad0e6c 100644
--- a/src/observer/sql/operator/expr_vec_physical_operator.h
+++ b/src/observer/sql/operator/expr_vec_physical_operator.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 表达式物理算子(Vectorized)
  * @ingroup PhysicalOperator
@@ -34,3 +36,4 @@ class ExprVecPhysicalOperator : public PhysicalOperator
   Chunk                chunk_;
   Chunk                evaled_chunk_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/group_by_logical_operator.cpp b/src/observer/sql/operator/group_by_logical_operator.cpp
index 5d86d847c..3ac7cfe91 100644
--- a/src/observer/sql/operator/group_by_logical_operator.cpp
+++ b/src/observer/sql/operator/group_by_logical_operator.cpp
@@ -18,9 +18,12 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
-GroupByLogicalOperator::GroupByLogicalOperator(vector<unique_ptr<Expression>> &&group_by_exprs,
-                                               vector<Expression *> &&expressions)
+namespace oceanbase {
+
+GroupByLogicalOperator::GroupByLogicalOperator(
+    vector<unique_ptr<Expression>> &&group_by_exprs, vector<Expression *> &&expressions)
 {
-  group_by_expressions_ = std::move(group_by_exprs);
+  group_by_expressions_  = std::move(group_by_exprs);
   aggregate_expressions_ = std::move(expressions);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/group_by_logical_operator.h b/src/observer/sql/operator/group_by_logical_operator.h
index 6e533e906..e3248d188 100644
--- a/src/observer/sql/operator/group_by_logical_operator.h
+++ b/src/observer/sql/operator/group_by_logical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 class GroupByLogicalOperator : public LogicalOperator
 {
 public:
@@ -33,3 +35,4 @@ class GroupByLogicalOperator : public LogicalOperator
   vector<unique_ptr<Expression>> group_by_expressions_;
   vector<Expression *>           aggregate_expressions_;  ///< 输出的表达式，可能包含聚合函数
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/group_by_physical_operator.cpp b/src/observer/sql/operator/group_by_physical_operator.cpp
index 75301f2b6..3457be317 100644
--- a/src/observer/sql/operator/group_by_physical_operator.cpp
+++ b/src/observer/sql/operator/group_by_physical_operator.cpp
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 GroupByPhysicalOperator::GroupByPhysicalOperator(vector<Expression *> &&expressions)
 {
   aggregate_expressions_ = std::move(expressions);
@@ -102,3 +104,4 @@ RC GroupByPhysicalOperator::evaluate(GroupValueType &group_value)
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/group_by_physical_operator.h b/src/observer/sql/operator/group_by_physical_operator.h
index 5c7a8f3ef..48a07ed82 100644
--- a/src/observer/sql/operator/group_by_physical_operator.h
+++ b/src/observer/sql/operator/group_by_physical_operator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/expr/composite_tuple.h"
 
+namespace oceanbase {
+
 /**
  * @brief Group By 物理算子基类
  * @ingroup PhysicalOperator
@@ -56,3 +58,4 @@ class GroupByPhysicalOperator : public PhysicalOperator
   vector<Expression *> aggregate_expressions_;  /// 聚合表达式
   vector<Expression *> value_expressions_;      /// 计算聚合时的表达式
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/group_by_vec_physical_operator.h b/src/observer/sql/operator/group_by_vec_physical_operator.h
index fe00deec7..3889a5e12 100644
--- a/src/observer/sql/operator/group_by_vec_physical_operator.h
+++ b/src/observer/sql/operator/group_by_vec_physical_operator.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/aggregate_hash_table.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief Group By 物理算子(vectorized)
  * @ingroup PhysicalOperator
@@ -20,7 +22,7 @@ See the Mulan PSL v2 for more details. */
 class GroupByVecPhysicalOperator : public PhysicalOperator
 {
 public:
-  GroupByVecPhysicalOperator(vector<unique_ptr<Expression>> &&group_by_exprs, vector<Expression *> &&expressions){};
+  GroupByVecPhysicalOperator(vector<unique_ptr<Expression>> &&group_by_exprs, vector<Expression *> &&expressions) {};
 
   virtual ~GroupByVecPhysicalOperator() = default;
 
@@ -32,3 +34,4 @@ class GroupByVecPhysicalOperator : public PhysicalOperator
 
 private:
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/hash_group_by_physical_operator.cpp b/src/observer/sql/operator/hash_group_by_physical_operator.cpp
index f408c0ec9..e8bb88c1e 100644
--- a/src/observer/sql/operator/hash_group_by_physical_operator.cpp
+++ b/src/observer/sql/operator/hash_group_by_physical_operator.cpp
@@ -20,11 +20,12 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 HashGroupByPhysicalOperator::HashGroupByPhysicalOperator(
     vector<unique_ptr<Expression>> &&group_by_exprs, vector<Expression *> &&expressions)
     : GroupByPhysicalOperator(std::move(expressions)), group_by_exprs_(std::move(group_by_exprs))
-{
-}
+{}
 
 RC HashGroupByPhysicalOperator::open(Trx *trx)
 {
@@ -61,7 +62,7 @@ RC HashGroupByPhysicalOperator::open(Trx *trx)
 
     // 计算聚合值
     GroupValueType &group_value = get<1>(*found_group);
-    rc = aggregate(get<0>(group_value), group_value_expression_tuple);
+    rc                          = aggregate(get<0>(group_value), group_value_expression_tuple);
     if (OB_FAIL(rc)) {
       LOG_WARN("failed to aggregate values. rc=%s", strrc(rc));
       return rc;
@@ -80,7 +81,7 @@ RC HashGroupByPhysicalOperator::open(Trx *trx)
   // 得到最终聚合后的值
   for (GroupType &group : groups_) {
     GroupValueType &group_value = get<1>(group);
-    rc = evaluate(group_value);
+    rc                          = evaluate(group_value);
     if (OB_FAIL(rc)) {
       LOG_WARN("failed to evaluate group value. rc=%s", strrc(rc));
       return rc;
@@ -170,10 +171,11 @@ RC HashGroupByPhysicalOperator::find_group(const Tuple &child_tuple, GroupType *
 
     CompositeTuple composite_tuple;
     composite_tuple.add_tuple(make_unique<ValueListTuple>(std::move(child_tuple_to_value)));
-    groups_.emplace_back(std::move(group_by_evaluated_tuple), 
-                         GroupValueType(std::move(aggregator_list), std::move(composite_tuple)));
+    groups_.emplace_back(
+        std::move(group_by_evaluated_tuple), GroupValueType(std::move(aggregator_list), std::move(composite_tuple)));
     found_group = &groups_.back();
   }
 
   return rc;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/hash_group_by_physical_operator.h b/src/observer/sql/operator/hash_group_by_physical_operator.h
index 36431d5a9..db85d63f3 100644
--- a/src/observer/sql/operator/hash_group_by_physical_operator.h
+++ b/src/observer/sql/operator/hash_group_by_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/group_by_physical_operator.h"
 #include "sql/expr/composite_tuple.h"
 
+namespace oceanbase {
+
 /**
  * @brief Group By Hash 方式物理算子
  * @ingroup PhysicalOperator
@@ -60,3 +62,4 @@ class HashGroupByPhysicalOperator : public GroupByPhysicalOperator
   vector<GroupType>::iterator current_group_;
   bool                        first_emited_ = false;  /// 第一条数据是否已经输出
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/hash_join_physical_operator.h b/src/observer/sql/operator/hash_join_physical_operator.h
index 4c7879aaa..287ce0958 100644
--- a/src/observer/sql/operator/hash_join_physical_operator.h
+++ b/src/observer/sql/operator/hash_join_physical_operator.h
@@ -13,9 +13,12 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/parser/parse.h"
 
+namespace oceanbase {
+
 /**
  * @brief Hash Join 算子
  * @ingroup PhysicalOperator
  */
 class HashJoinPhysicalOperator
-{};
\ No newline at end of file
+{};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/index_scan_physical_operator.cpp b/src/observer/sql/operator/index_scan_physical_operator.cpp
index 01cf7eb79..cb78d9bb4 100644
--- a/src/observer/sql/operator/index_scan_physical_operator.cpp
+++ b/src/observer/sql/operator/index_scan_physical_operator.cpp
@@ -16,13 +16,11 @@ See the Mulan PSL v2 for more details. */
 #include "storage/index/index.h"
 #include "storage/trx/trx.h"
 
-IndexScanPhysicalOperator::IndexScanPhysicalOperator(Table *table, Index *index, ReadWriteMode mode, const Value *left_value,
-    bool left_inclusive, const Value *right_value, bool right_inclusive)
-    : table_(table),
-      index_(index),
-      mode_(mode),
-      left_inclusive_(left_inclusive),
-      right_inclusive_(right_inclusive)
+namespace oceanbase {
+
+IndexScanPhysicalOperator::IndexScanPhysicalOperator(Table *table, Index *index, ReadWriteMode mode,
+    const Value *left_value, bool left_inclusive, const Value *right_value, bool right_inclusive)
+    : table_(table), index_(index), mode_(mode), left_inclusive_(left_inclusive), right_inclusive_(right_inclusive)
 {
   if (left_value) {
     left_value_ = *left_value;
@@ -139,3 +137,4 @@ string IndexScanPhysicalOperator::param() const
 {
   return string(index_->index_meta().name()) + " ON " + table_->name();
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/index_scan_physical_operator.h b/src/observer/sql/operator/index_scan_physical_operator.h
index 405e74716..1d37b99ff 100644
--- a/src/observer/sql/operator/index_scan_physical_operator.h
+++ b/src/observer/sql/operator/index_scan_physical_operator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "storage/record/record_manager.h"
 
+namespace oceanbase {
+
 /**
  * @brief 索引扫描物理算子
  * @ingroup PhysicalOperator
@@ -63,3 +65,4 @@ class IndexScanPhysicalOperator : public PhysicalOperator
 
   vector<unique_ptr<Expression>> predicates_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/insert_logical_operator.cpp b/src/observer/sql/operator/insert_logical_operator.cpp
index 51ad27a2e..6b8824eef 100644
--- a/src/observer/sql/operator/insert_logical_operator.cpp
+++ b/src/observer/sql/operator/insert_logical_operator.cpp
@@ -14,5 +14,7 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/insert_logical_operator.h"
 
-InsertLogicalOperator::InsertLogicalOperator(Table *table, vector<Value> values) : table_(table), values_(values)
-{}
+namespace oceanbase {
+
+InsertLogicalOperator::InsertLogicalOperator(Table *table, vector<Value> values) : table_(table), values_(values) {}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/insert_logical_operator.h b/src/observer/sql/operator/insert_logical_operator.h
index 72df40ac5..6e2f23072 100644
--- a/src/observer/sql/operator/insert_logical_operator.h
+++ b/src/observer/sql/operator/insert_logical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/logical_operator.h"
 #include "sql/parser/parse_defs.h"
 
+namespace oceanbase {
+
 /**
  * @brief 插入逻辑算子
  * @ingroup LogicalOperator
@@ -39,3 +41,4 @@ class InsertLogicalOperator : public LogicalOperator
   Table        *table_ = nullptr;
   vector<Value> values_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/insert_physical_operator.cpp b/src/observer/sql/operator/insert_physical_operator.cpp
index fd1bc9085..31376b9c8 100644
--- a/src/observer/sql/operator/insert_physical_operator.cpp
+++ b/src/observer/sql/operator/insert_physical_operator.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 InsertPhysicalOperator::InsertPhysicalOperator(Table *table, vector<Value> &&values)
     : table_(table), values_(std::move(values))
 {}
@@ -42,3 +44,4 @@ RC InsertPhysicalOperator::open(Trx *trx)
 RC InsertPhysicalOperator::next() { return RC::RECORD_EOF; }
 
 RC InsertPhysicalOperator::close() { return RC::SUCCESS; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/insert_physical_operator.h b/src/observer/sql/operator/insert_physical_operator.h
index 85aedc6e5..cf5bb2e68 100644
--- a/src/observer/sql/operator/insert_physical_operator.h
+++ b/src/observer/sql/operator/insert_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/parser/parse.h"
 
+namespace oceanbase {
+
 class InsertStmt;
 
 /**
@@ -44,3 +46,4 @@ class InsertPhysicalOperator : public PhysicalOperator
   Table        *table_ = nullptr;
   vector<Value> values_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/join_logical_operator.h b/src/observer/sql/operator/join_logical_operator.h
index deec7bcd8..02bc85451 100644
--- a/src/observer/sql/operator/join_logical_operator.h
+++ b/src/observer/sql/operator/join_logical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 连接算子
  * @ingroup LogicalOperator
@@ -73,3 +75,4 @@ class JoinLogicalOperator : public LogicalOperator
   LogicalOperator                    *predicate_op_ = nullptr;
   std::vector<unique_ptr<Expression>> join_predicates_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/join_physical_operator.cpp b/src/observer/sql/operator/join_physical_operator.cpp
index 0de387301..6d4216490 100644
--- a/src/observer/sql/operator/join_physical_operator.cpp
+++ b/src/observer/sql/operator/join_physical_operator.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/join_physical_operator.h"
 
+namespace oceanbase {
+
 NestedLoopJoinPhysicalOperator::NestedLoopJoinPhysicalOperator() {}
 
 RC NestedLoopJoinPhysicalOperator::open(Trx *trx)
@@ -131,3 +133,4 @@ RC NestedLoopJoinPhysicalOperator::right_next()
   joined_tuple_.set_right(right_tuple_);
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/join_physical_operator.h b/src/observer/sql/operator/join_physical_operator.h
index 930d5f194..1cd46f717 100644
--- a/src/observer/sql/operator/join_physical_operator.h
+++ b/src/observer/sql/operator/join_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/parser/parse.h"
 
+namespace oceanbase {
+
 /**
  * @brief 最简单的两表（称为左表、右表）join算子
  * @details 依次遍历左表的每一行，然后关联右表的每一行
@@ -51,3 +53,4 @@ class NestedLoopJoinPhysicalOperator : public PhysicalOperator
   bool              round_done_   = true;  //! 右表遍历的一轮是否结束
   bool              right_closed_ = true;  //! 右表算子是否已经关闭
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/logical_operator.cpp b/src/observer/sql/operator/logical_operator.cpp
index a2fb251db..87ac2248e 100644
--- a/src/observer/sql/operator/logical_operator.cpp
+++ b/src/observer/sql/operator/logical_operator.cpp
@@ -14,26 +14,21 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 LogicalOperator::~LogicalOperator() {}
 
-void LogicalOperator::add_child(unique_ptr<LogicalOperator> oper) {
-  children_.emplace_back(std::move(oper));
-}
+void LogicalOperator::add_child(unique_ptr<LogicalOperator> oper) { children_.emplace_back(std::move(oper)); }
 void LogicalOperator::add_expressions(unique_ptr<Expression> expr) { expressions_.emplace_back(std::move(expr)); }
 bool LogicalOperator::can_generate_vectorized_operator(const LogicalOperatorType &type)
 {
   bool bool_ret = false;
-  switch (type)
-  {
-  case LogicalOperatorType::CALC:
-  case LogicalOperatorType::DELETE:
-  case LogicalOperatorType::INSERT:
-    bool_ret = false;
-    break;
-  
-  default:
-    bool_ret = true;
-    break;
+  switch (type) {
+    case LogicalOperatorType::CALC:
+    case LogicalOperatorType::DELETE:
+    case LogicalOperatorType::INSERT: bool_ret = false; break;
+
+    default: bool_ret = true; break;
   }
   return bool_ret;
 }
@@ -45,4 +40,4 @@ void LogicalOperator::generate_general_child()
     child->generate_general_child();
   }
 }
-
+}  // namespace oceanbase
diff --git a/src/observer/sql/operator/logical_operator.h b/src/observer/sql/operator/logical_operator.h
index d212dbcc2..dd8ff4993 100644
--- a/src/observer/sql/operator/logical_operator.h
+++ b/src/observer/sql/operator/logical_operator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/operator_node.h"
 #include "common/lang/unordered_set.h"
 
+namespace oceanbase {
+
 /**
  * @brief 逻辑算子
  * @defgroup LogicalOperator
@@ -72,3 +74,4 @@ class LogicalOperator : public OperatorNode
   ///< 表达式能是一个常量，也可以是一个函数，也可以是一个列，也可以是一个子查询等等
   vector<unique_ptr<Expression>> expressions_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/nested_loop_join_physical_operator.cpp b/src/observer/sql/operator/nested_loop_join_physical_operator.cpp
index 5228d23fd..24c7b62c5 100644
--- a/src/observer/sql/operator/nested_loop_join_physical_operator.cpp
+++ b/src/observer/sql/operator/nested_loop_join_physical_operator.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/nested_loop_join_physical_operator.h"
 
+namespace oceanbase {
+
 NestedLoopJoinPhysicalOperator::NestedLoopJoinPhysicalOperator() {}
 
 RC NestedLoopJoinPhysicalOperator::open(Trx *trx)
@@ -36,7 +38,7 @@ RC NestedLoopJoinPhysicalOperator::open(Trx *trx)
 
 RC NestedLoopJoinPhysicalOperator::next()
 {
-  RC   rc             = RC::SUCCESS;
+  RC rc = RC::SUCCESS;
   while (RC::SUCCESS == rc) {
     bool left_need_step = (left_tuple_ == nullptr);
     if (round_done_) {
@@ -53,7 +55,7 @@ RC NestedLoopJoinPhysicalOperator::next()
     rc = right_next();
     if (rc != RC::SUCCESS) {
       if (rc == RC::RECORD_EOF) {
-        rc = RC::SUCCESS;
+        rc          = RC::SUCCESS;
         round_done_ = true;
         continue;
       } else {
@@ -131,3 +133,4 @@ RC NestedLoopJoinPhysicalOperator::right_next()
   joined_tuple_.set_right(right_tuple_);
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/nested_loop_join_physical_operator.h b/src/observer/sql/operator/nested_loop_join_physical_operator.h
index 80b455975..edb979f25 100644
--- a/src/observer/sql/operator/nested_loop_join_physical_operator.h
+++ b/src/observer/sql/operator/nested_loop_join_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/parser/parse.h"
 
+namespace oceanbase {
+
 /**
  * @brief 最简单的两表（称为左表、右表）join算子
  * @details 依次遍历左表的每一行，然后关联右表的每一行
@@ -62,3 +64,4 @@ class NestedLoopJoinPhysicalOperator : public PhysicalOperator
   bool              round_done_   = true;  //! 右表遍历的一轮是否结束
   bool              right_closed_ = true;  //! 右表算子是否已经关闭
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/operator_node.h b/src/observer/sql/operator/operator_node.h
index f349f4b00..4f9321024 100644
--- a/src/observer/sql/operator/operator_node.h
+++ b/src/observer/sql/operator/operator_node.h
@@ -15,6 +15,9 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/memory.h"
 #include "sql/optimizer/cascade/property.h"
 #include "sql/optimizer/cascade/cost_model.h"
+
+namespace oceanbase {
+
 /**
  * @brief Operator type(including logical and physical)
  */
@@ -141,4 +144,5 @@ class OperatorNode
   // TODO: refactor
   // cascade optimizer 中使用，为了logical/physical operator 可以统一在 cascade 中迭代
   vector<OperatorNode *> general_children_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/physical_operator.cpp b/src/observer/sql/operator/physical_operator.cpp
index 7ff99d67c..2406ba7c1 100644
--- a/src/observer/sql/operator/physical_operator.cpp
+++ b/src/observer/sql/operator/physical_operator.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 string physical_operator_type_name(PhysicalOperatorType type)
 {
   switch (type) {
@@ -41,3 +43,4 @@ string physical_operator_type_name(PhysicalOperatorType type)
 string PhysicalOperator::name() const { return physical_operator_type_name(type()); }
 
 string PhysicalOperator::param() const { return ""; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/physical_operator.h b/src/observer/sql/operator/physical_operator.h
index 8f2b67ba1..16cbaf443 100644
--- a/src/observer/sql/operator/physical_operator.h
+++ b/src/observer/sql/operator/physical_operator.h
@@ -22,6 +22,8 @@ class Record;
 class TupleCellSpec;
 class Trx;
 
+namespace oceanbase {
+
 /**
  * @brief 物理算子
  * @defgroup PhysicalOperator
@@ -93,3 +95,4 @@ class PhysicalOperator : public OperatorNode
 protected:
   vector<unique_ptr<PhysicalOperator>> children_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/predicate_logical_operator.cpp b/src/observer/sql/operator/predicate_logical_operator.cpp
index e7db87c77..ea427e1b9 100644
--- a/src/observer/sql/operator/predicate_logical_operator.cpp
+++ b/src/observer/sql/operator/predicate_logical_operator.cpp
@@ -14,7 +14,10 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/predicate_logical_operator.h"
 
+namespace oceanbase {
+
 PredicateLogicalOperator::PredicateLogicalOperator(unique_ptr<Expression> expression)
 {
   expressions_.emplace_back(std::move(expression));
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/predicate_logical_operator.h b/src/observer/sql/operator/predicate_logical_operator.h
index 115121ff9..05f5901a9 100644
--- a/src/observer/sql/operator/predicate_logical_operator.h
+++ b/src/observer/sql/operator/predicate_logical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/expression.h"
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 谓词/过滤逻辑算子
  * @ingroup LogicalOperator
@@ -31,3 +33,4 @@ class PredicateLogicalOperator : public LogicalOperator
 
   OpType get_op_type() const override { return OpType::LOGICALFILTER; }
 };
+}  // namespace oceanbase
diff --git a/src/observer/sql/operator/predicate_physical_operator.cpp b/src/observer/sql/operator/predicate_physical_operator.cpp
index 61b564451..e911e2fae 100644
--- a/src/observer/sql/operator/predicate_physical_operator.cpp
+++ b/src/observer/sql/operator/predicate_physical_operator.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/field/field.h"
 #include "storage/record/record.h"
 
+namespace oceanbase {
+
 PredicatePhysicalOperator::PredicatePhysicalOperator(std::unique_ptr<Expression> expr) : expression_(std::move(expr))
 {
   ASSERT(expression_->value_type() == AttrType::BOOLEANS, "predicate's expression should be BOOLEAN type");
@@ -67,7 +69,5 @@ RC PredicatePhysicalOperator::close()
 
 Tuple *PredicatePhysicalOperator::current_tuple() { return children_[0]->current_tuple(); }
 
-RC PredicatePhysicalOperator::tuple_schema(TupleSchema &schema) const
-{
-  return children_[0]->tuple_schema(schema);
-}
+RC PredicatePhysicalOperator::tuple_schema(TupleSchema &schema) const { return children_[0]->tuple_schema(schema); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/predicate_physical_operator.h b/src/observer/sql/operator/predicate_physical_operator.h
index 49bbcbfbd..10ac20d36 100644
--- a/src/observer/sql/operator/predicate_physical_operator.h
+++ b/src/observer/sql/operator/predicate_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/expression.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class FilterStmt;
 
 /**
@@ -44,3 +46,4 @@ class PredicatePhysicalOperator : public PhysicalOperator
 private:
   unique_ptr<Expression> expression_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/project_logical_operator.cpp b/src/observer/sql/operator/project_logical_operator.cpp
index bbd06d1be..3594e9e34 100644
--- a/src/observer/sql/operator/project_logical_operator.cpp
+++ b/src/observer/sql/operator/project_logical_operator.cpp
@@ -16,12 +16,14 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 ProjectLogicalOperator::ProjectLogicalOperator(vector<unique_ptr<Expression>> &&expressions)
 {
   expressions_ = std::move(expressions);
 }
 
-unique_ptr<LogicalProperty> ProjectLogicalOperator::find_log_prop(const vector<LogicalProperty*> &log_props)
+unique_ptr<LogicalProperty> ProjectLogicalOperator::find_log_prop(const vector<LogicalProperty *> &log_props)
 {
   int card = 0;
   for (auto log_prop : log_props) {
@@ -33,3 +35,4 @@ unique_ptr<LogicalProperty> ProjectLogicalOperator::find_log_prop(const vector<L
   }
   return make_unique<LogicalProperty>(card);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/project_logical_operator.h b/src/observer/sql/operator/project_logical_operator.h
index 6522ac3c1..98369db38 100644
--- a/src/observer/sql/operator/project_logical_operator.h
+++ b/src/observer/sql/operator/project_logical_operator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/logical_operator.h"
 #include "storage/field/field.h"
 
+namespace oceanbase {
+
 /**
  * @brief project 表示投影运算
  * @ingroup LogicalOperator
@@ -36,3 +38,4 @@ class ProjectLogicalOperator : public LogicalOperator
   vector<unique_ptr<Expression>>       &expressions() { return expressions_; }
   const vector<unique_ptr<Expression>> &expressions() const { return expressions_; }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/project_physical_operator.cpp b/src/observer/sql/operator/project_physical_operator.cpp
index 9c06125b6..265f7a50e 100644
--- a/src/observer/sql/operator/project_physical_operator.cpp
+++ b/src/observer/sql/operator/project_physical_operator.cpp
@@ -19,10 +19,11 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 ProjectPhysicalOperator::ProjectPhysicalOperator(vector<unique_ptr<Expression>> &&expressions)
-  : expressions_(std::move(expressions)), tuple_(expressions_)
-{
-}
+    : expressions_(std::move(expressions)), tuple_(expressions_)
+{}
 
 RC ProjectPhysicalOperator::open(Trx *trx)
 {
@@ -67,4 +68,5 @@ RC ProjectPhysicalOperator::tuple_schema(TupleSchema &schema) const
     schema.append_cell(expression->name());
   }
   return RC::SUCCESS;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/project_physical_operator.h b/src/observer/sql/operator/project_physical_operator.h
index 781e4ee11..6e4d9e6cc 100644
--- a/src/observer/sql/operator/project_physical_operator.h
+++ b/src/observer/sql/operator/project_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/expr/expression_tuple.h"
 
+namespace oceanbase {
+
 /**
  * @brief 选择/投影物理算子
  * @ingroup PhysicalOperator
@@ -51,3 +53,4 @@ class ProjectPhysicalOperator : public PhysicalOperator
   vector<unique_ptr<Expression>>          expressions_;
   ExpressionTuple<unique_ptr<Expression>> tuple_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/project_vec_physical_operator.cpp b/src/observer/sql/operator/project_vec_physical_operator.cpp
index 06a487cfb..bfc5498d2 100644
--- a/src/observer/sql/operator/project_vec_physical_operator.cpp
+++ b/src/observer/sql/operator/project_vec_physical_operator.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 ProjectVecPhysicalOperator::ProjectVecPhysicalOperator(vector<unique_ptr<Expression>> &&expressions)
     : expressions_(std::move(expressions))
 {
@@ -71,3 +73,4 @@ RC ProjectVecPhysicalOperator::tuple_schema(TupleSchema &schema) const
   }
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/project_vec_physical_operator.h b/src/observer/sql/operator/project_vec_physical_operator.h
index de3f716f6..acb95f5e5 100644
--- a/src/observer/sql/operator/project_vec_physical_operator.h
+++ b/src/observer/sql/operator/project_vec_physical_operator.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/expr/expression_tuple.h"
 
+namespace oceanbase {
+
 /**
  * @brief 选择/投影物理算子(vectorized)
  * @ingroup PhysicalOperator
@@ -39,3 +41,4 @@ class ProjectVecPhysicalOperator : public PhysicalOperator
   vector<unique_ptr<Expression>> expressions_;
   Chunk                          chunk_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/scalar_group_by_physical_operator.cpp b/src/observer/sql/operator/scalar_group_by_physical_operator.cpp
index d07546dbe..496f9df9c 100644
--- a/src/observer/sql/operator/scalar_group_by_physical_operator.cpp
+++ b/src/observer/sql/operator/scalar_group_by_physical_operator.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 ScalarGroupByPhysicalOperator::ScalarGroupByPhysicalOperator(vector<Expression *> &&expressions)
     : GroupByPhysicalOperator(std::move(expressions))
 {}
@@ -65,7 +67,7 @@ RC ScalarGroupByPhysicalOperator::open(Trx *trx)
       composite_tuple.add_tuple(make_unique<ValueListTuple>(std::move(child_tuple_to_value)));
       group_value_ = make_unique<GroupValueType>(std::move(aggregator_list), std::move(composite_tuple));
     }
-    
+
     rc = aggregate(get<0>(*group_value_), group_value_expression_tuple);
     if (OB_FAIL(rc)) {
       LOG_WARN("failed to aggregate values. rc=%s", strrc(rc));
@@ -117,4 +119,5 @@ Tuple *ScalarGroupByPhysicalOperator::current_tuple()
   }
 
   return &get<1>(*group_value_);
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/scalar_group_by_physical_operator.h b/src/observer/sql/operator/scalar_group_by_physical_operator.h
index d55d3c507..9d1ddb459 100644
--- a/src/observer/sql/operator/scalar_group_by_physical_operator.h
+++ b/src/observer/sql/operator/scalar_group_by_physical_operator.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/operator/group_by_physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 没有 group by 表达式的 group by 物理算子
  * @ingroup PhysicalOperator
@@ -39,3 +41,4 @@ class ScalarGroupByPhysicalOperator : public GroupByPhysicalOperator
   unique_ptr<GroupValueType> group_value_;
   bool                       emitted_ = false;  /// 标识是否已经输出过
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/string_list_physical_operator.h b/src/observer/sql/operator/string_list_physical_operator.h
index 038aa0bea..e872f8546 100644
--- a/src/observer/sql/operator/string_list_physical_operator.h
+++ b/src/observer/sql/operator/string_list_physical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/initializer_list.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 /**
  * @brief 字符串列表物理算子
  * @ingroup PhysicalOperator
@@ -89,3 +91,4 @@ class StringListPhysicalOperator : public PhysicalOperator
   bool                     started_ = false;
   ValueListTuple           tuple_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/table_get_logical_operator.cpp b/src/observer/sql/operator/table_get_logical_operator.cpp
index 9917062b0..eaa2d61ff 100644
--- a/src/observer/sql/operator/table_get_logical_operator.cpp
+++ b/src/observer/sql/operator/table_get_logical_operator.cpp
@@ -16,18 +16,18 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/property.h"
 #include "catalog/catalog.h"
 
+namespace oceanbase {
+
 TableGetLogicalOperator::TableGetLogicalOperator(Table *table, ReadWriteMode mode)
     : LogicalOperator(), table_(table), mode_(mode)
 {}
 
-void TableGetLogicalOperator::set_predicates(vector<unique_ptr<Expression>> &&exprs)
-{
-  predicates_ = std::move(exprs);
-}
+void TableGetLogicalOperator::set_predicates(vector<unique_ptr<Expression>> &&exprs) { predicates_ = std::move(exprs); }
 
-unique_ptr<LogicalProperty> TableGetLogicalOperator::find_log_prop(const vector<LogicalProperty*> &log_props)
+unique_ptr<LogicalProperty> TableGetLogicalOperator::find_log_prop(const vector<LogicalProperty *> &log_props)
 {
   int card = Catalog::get_instance().get_table_stats(table_->table_id()).row_nums;
   // TODO: think about predicates.
   return make_unique<LogicalProperty>(card);
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/table_get_logical_operator.h b/src/observer/sql/operator/table_get_logical_operator.h
index a95c25337..22808cf2e 100644
--- a/src/observer/sql/operator/table_get_logical_operator.h
+++ b/src/observer/sql/operator/table_get_logical_operator.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/field/field.h"
 #include "common/types.h"
 
+namespace oceanbase {
+
 /**
  * @brief 表示从表中获取数据的算子
  * @details 比如使用全表扫描、通过索引获取数据等
@@ -67,3 +69,4 @@ class TableGetLogicalOperator : public LogicalOperator
   // 如果有多个表达式，他们的关系都是 AND
   vector<unique_ptr<Expression>> predicates_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/table_scan_physical_operator.cpp b/src/observer/sql/operator/table_scan_physical_operator.cpp
index 895966e23..b720ea8b9 100644
--- a/src/observer/sql/operator/table_scan_physical_operator.cpp
+++ b/src/observer/sql/operator/table_scan_physical_operator.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC TableScanPhysicalOperator::open(Trx *trx)
 {
   RC rc = table_->get_record_scanner(record_scanner_, trx, mode_);
@@ -35,7 +37,7 @@ RC TableScanPhysicalOperator::next()
   bool filter_result = false;
   while (OB_SUCC(rc = record_scanner_->next(current_record_))) {
     LOG_TRACE("got a record. rid=%s", current_record_.rid().to_string().c_str());
-    
+
     tuple_.set_record(&current_record_);
     rc = filter(tuple_, filter_result);
     if (rc != RC::SUCCESS) {
@@ -53,7 +55,8 @@ RC TableScanPhysicalOperator::next()
   return rc;
 }
 
-RC TableScanPhysicalOperator::close() {
+RC TableScanPhysicalOperator::close()
+{
   RC rc = RC::SUCCESS;
   if (record_scanner_ != nullptr) {
     rc = record_scanner_->close_scan();
@@ -64,7 +67,6 @@ RC TableScanPhysicalOperator::close() {
     record_scanner_ = nullptr;
   }
   return rc;
-
 }
 
 Tuple *TableScanPhysicalOperator::current_tuple()
@@ -100,3 +102,4 @@ RC TableScanPhysicalOperator::filter(RowTuple &tuple, bool &result)
   result = true;
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/table_scan_physical_operator.h b/src/observer/sql/operator/table_scan_physical_operator.h
index d62e8e483..673206cb7 100644
--- a/src/observer/sql/operator/table_scan_physical_operator.h
+++ b/src/observer/sql/operator/table_scan_physical_operator.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/record_scanner.h"
 #include "common/types.h"
 
+namespace oceanbase {
+
 class Table;
 
 /**
@@ -81,3 +83,4 @@ class TableScanPhysicalOperator : public PhysicalOperator
   RowTuple                       tuple_;
   vector<unique_ptr<Expression>> predicates_;  // TODO chang predicate to table tuple filter
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/operator/table_scan_vec_physical_operator.cpp b/src/observer/sql/operator/table_scan_vec_physical_operator.cpp
index 9744776cd..9ae9d5260 100644
--- a/src/observer/sql/operator/table_scan_vec_physical_operator.cpp
+++ b/src/observer/sql/operator/table_scan_vec_physical_operator.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 RC TableScanVecPhysicalOperator::open(Trx *trx)
 {
   RC rc = table_->get_chunk_scanner(chunk_scanner_, trx, mode_);
@@ -53,8 +55,7 @@ RC TableScanVecPhysicalOperator::next(Chunk &chunk)
           continue;
         }
         for (int j = 0; j < all_columns_.column_num(); j++) {
-          filterd_columns_.column(j).append_value(
-              all_columns_.column(filterd_columns_.column_ids(j)).get_value(i));
+          filterd_columns_.column(j).append_value(all_columns_.column(filterd_columns_.column_ids(j)).get_value(i));
         }
       }
       chunk.reference(filterd_columns_);
@@ -83,3 +84,4 @@ RC TableScanVecPhysicalOperator::filter(Chunk &chunk)
   }
   return rc;
 }
+}  // namespace oceanbase
diff --git a/src/observer/sql/operator/table_scan_vec_physical_operator.h b/src/observer/sql/operator/table_scan_vec_physical_operator.h
index 8982055dd..28b21f88b 100644
--- a/src/observer/sql/operator/table_scan_vec_physical_operator.h
+++ b/src/observer/sql/operator/table_scan_vec_physical_operator.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/record_manager.h"
 #include "common/types.h"
 
+namespace oceanbase {
+
 class Table;
 
 /**
@@ -50,3 +52,4 @@ class TableScanVecPhysicalOperator : public PhysicalOperator
   vector<uint8_t>                select_;
   vector<unique_ptr<Expression>> predicates_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/cost_model.cpp b/src/observer/sql/optimizer/cascade/cost_model.cpp
index 16f43ec7f..48b296a22 100644
--- a/src/observer/sql/optimizer/cascade/cost_model.cpp
+++ b/src/observer/sql/optimizer/cascade/cost_model.cpp
@@ -13,18 +13,19 @@ See the Mulan PSL v2 for more details. */
 #include "catalog/catalog.h"
 #include "sql/optimizer/cascade/group_expr.h"
 
-double CostModel::calculate_cost(Memo *memo,
-                               GroupExpr *gexpr)
+namespace oceanbase {
+
+double CostModel::calculate_cost(Memo *memo, GroupExpr *gexpr)
 {
-  auto op = gexpr->get_op();
-  auto log_prop = memo->get_group_by_id(gexpr->get_group_id())->get_logical_prop();
-  int arity = gexpr->get_children_groups_size();
-  vector<LogicalProperty*> child_log_props;
+  auto                      op       = gexpr->get_op();
+  auto                      log_prop = memo->get_group_by_id(gexpr->get_group_id())->get_logical_prop();
+  int                       arity    = gexpr->get_children_groups_size();
+  vector<LogicalProperty *> child_log_props;
   for (int i = 0; i < arity; ++i) {
     auto child_group_id = gexpr->get_child_group_id(i);
-    auto child_gexpr = memo->get_group_by_id(child_group_id);
+    auto child_gexpr    = memo->get_group_by_id(child_group_id);
     child_log_props.push_back(child_gexpr->get_logical_prop());
   }
   return op->calculate_cost(log_prop, child_log_props, this);
-
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/cost_model.h b/src/observer/sql/optimizer/cascade/cost_model.h
index e64284ec8..2d17e8e5e 100644
--- a/src/observer/sql/optimizer/cascade/cost_model.h
+++ b/src/observer/sql/optimizer/cascade/cost_model.h
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 class Memo;
 class GroupExpr;
 /**
@@ -27,7 +29,7 @@ class CostModel
 
 public:
   // TODO: support user-defined
-  CostModel(){};
+  CostModel() {}
 
   inline double cpu_op() { return CPU_OP; }
 
@@ -44,4 +46,5 @@ class CostModel
   inline double io() { return IO; }
 
   double calculate_cost(Memo *memo, GroupExpr *gexpr);
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/group.cpp b/src/observer/sql/optimizer/cascade/group.cpp
index fab245d1a..2b9cfdbd6 100644
--- a/src/observer/sql/optimizer/cascade/group.cpp
+++ b/src/observer/sql/optimizer/cascade/group.cpp
@@ -12,24 +12,26 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/group_expr.h"
 #include "sql/optimizer/cascade/memo.h"
 
-Group::Group(int id, GroupExpr* expr, Memo *memo)
-      : id_(id), winner_(std::make_tuple(numeric_limits<double>::max(), nullptr)), has_explored_(false)
+namespace oceanbase {
+
+Group::Group(int id, GroupExpr *expr, Memo *memo)
+    : id_(id), winner_(std::make_tuple(numeric_limits<double>::max(), nullptr)), has_explored_(false)
 {
-  int arity = expr->get_children_groups_size();
-	vector<LogicalProperty*> input_prop;
-	if(arity == 0) {
+  int                       arity = expr->get_children_groups_size();
+  vector<LogicalProperty *> input_prop;
+  if (arity == 0) {
+    logical_prop_ = (expr->get_op())->find_log_prop(input_prop);
+  } else {
+    for (int i = 0; i < arity; i++) {
+      auto group = memo->get_group_by_id(expr->get_child_group_id(i));
+      input_prop.push_back(group->get_logical_prop());
+    }
+
     logical_prop_ = (expr->get_op())->find_log_prop(input_prop);
-	} else {
-		for(int i=0; i<arity; i++)
-		{	
-			auto group = memo->get_group_by_id(expr->get_child_group_id(i));
-			input_prop.push_back(group->get_logical_prop());
-		}
-		
-		logical_prop_ = (expr->get_op())->find_log_prop(input_prop);
   }
 }
-Group::~Group() {
+Group::~Group()
+{
   for (auto expr : logical_expressions_) {
     delete expr;
   }
@@ -48,8 +50,8 @@ void Group::add_expr(GroupExpr *expr)
   }
 }
 
-bool Group::set_expr_cost(GroupExpr *expr, double cost) {
-  
+bool Group::set_expr_cost(GroupExpr *expr, double cost)
+{
 
   if (std::get<0>(winner_) > cost) {
     // this is lower cost
@@ -59,11 +61,10 @@ bool Group::set_expr_cost(GroupExpr *expr, double cost) {
   return false;
 }
 
-GroupExpr *Group::get_winner() {
-  return std::get<1>(winner_);
-}
+GroupExpr *Group::get_winner() { return std::get<1>(winner_); }
 
-GroupExpr *Group::get_logical_expression() {
+GroupExpr *Group::get_logical_expression()
+{
   ASSERT(logical_expressions_.size() == 1, "There should exist only 1 logical expression");
   ASSERT(physical_expressions_.empty(), "No physical expressions should be present");
   return logical_expressions_[0];
@@ -73,4 +74,5 @@ void Group::dump() const
 {
   LOG_TRACE("Group %d has %lu logical expressions and %lu physical expressions", 
            id_, logical_expressions_.size(), physical_expressions_.size(), physical_expressions_.size());
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/group.h b/src/observer/sql/optimizer/cascade/group.h
index bcecf58b1..eb50572f9 100644
--- a/src/observer/sql/optimizer/cascade/group.h
+++ b/src/observer/sql/optimizer/cascade/group.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/unordered_map.h"
 #include "sql/optimizer/cascade/property_set.h"
 
+namespace oceanbase {
+
 class GroupExpr;
 class Memo;
 /**
@@ -110,4 +112,5 @@ class Group
   std::vector<GroupExpr *> physical_expressions_;
 
   unique_ptr<LogicalProperty> logical_prop_ = nullptr;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/group_expr.cpp b/src/observer/sql/optimizer/cascade/group_expr.cpp
index be0e4aeba..96446ec6c 100644
--- a/src/observer/sql/optimizer/cascade/group_expr.cpp
+++ b/src/observer/sql/optimizer/cascade/group_expr.cpp
@@ -10,11 +10,14 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/cascade/group_expr.h"
 
+namespace oceanbase {
+
 uint64_t GroupExpr::hash() const
 {
   auto hash = contents_->hash();
   for (const auto &child : child_groups_) {
-    hash ^= std::hash<int>()(child) + 0x9e3779b9 + (hash << 6) + (hash >> 2);;
+    hash ^= std::hash<int>()(child) + 0x9e3779b9 + (hash << 6) + (hash >> 2);
+    ;
   }
   return hash;
 }
@@ -26,4 +29,5 @@ void GroupExpr::dump() const
     ss << child << " ";
   }
   LOG_TRACE("GroupExpr contents: %d child groups:  %s", static_cast<int>(contents_->get_op_type()), ss.str().c_str());
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/group_expr.h b/src/observer/sql/optimizer/cascade/group_expr.h
index c3d752dfb..ea913710d 100644
--- a/src/observer/sql/optimizer/cascade/group_expr.h
+++ b/src/observer/sql/optimizer/cascade/group_expr.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/rules.h"
 #include "sql/optimizer/cascade/property_set.h"
 
+namespace oceanbase {
+
 // TODO: rename to m_expr(in columbia)?
 /* GroupExpr used to represent a particular logical or physical
  * operator expression.
@@ -84,4 +86,5 @@ class GroupExpr
   std::bitset<static_cast<uint32_t>(RuleType::NUM_RULES)> rule_mask_;
 
   double lowest_cost_ = std::numeric_limits<double>::max();
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/implementation_rules.cpp b/src/observer/sql/optimizer/cascade/implementation_rules.cpp
index 740f44381..470dcf6c1 100644
--- a/src/observer/sql/optimizer/cascade/implementation_rules.cpp
+++ b/src/observer/sql/optimizer/cascade/implementation_rules.cpp
@@ -28,27 +28,30 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/scalar_group_by_physical_operator.h"
 #include "sql/operator/hash_group_by_physical_operator.h"
 
+namespace oceanbase {
+
 // -------------------------------------------------------------------------------------------------
 // PhysicalSeqScan
 // -------------------------------------------------------------------------------------------------
-LogicalGetToPhysicalSeqScan::LogicalGetToPhysicalSeqScan() {
-  type_ = RuleType::GET_TO_SEQ_SCAN;
+LogicalGetToPhysicalSeqScan::LogicalGetToPhysicalSeqScan()
+{
+  type_          = RuleType::GET_TO_SEQ_SCAN;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALGET));
 }
 
-void LogicalGetToPhysicalSeqScan::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const {
-  TableGetLogicalOperator* table_get_oper = dynamic_cast<TableGetLogicalOperator*>(input);
+void LogicalGetToPhysicalSeqScan::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
+{
+  TableGetLogicalOperator *table_get_oper = dynamic_cast<TableGetLogicalOperator *>(input);
 
   vector<unique_ptr<Expression>> &log_preds = table_get_oper->predicates();
-  vector<unique_ptr<Expression>> phys_preds;
+  vector<unique_ptr<Expression>>  phys_preds;
   for (auto &pred : log_preds) {
     phys_preds.push_back(pred->copy());
   }
 
-  Table *table = table_get_oper->table();
-  auto table_scan_oper = new TableScanPhysicalOperator(table, table_get_oper->read_write_mode());
+  Table *table           = table_get_oper->table();
+  auto   table_scan_oper = new TableScanPhysicalOperator(table, table_get_oper->read_write_mode());
   table_scan_oper->set_predicates(std::move(phys_preds));
   auto oper = unique_ptr<OperatorNode>(table_scan_oper);
 
@@ -58,18 +61,19 @@ void LogicalGetToPhysicalSeqScan::transform(OperatorNode* input,
 // -------------------------------------------------------------------------------------------------
 //  LogicalProjectionToProjection
 // -------------------------------------------------------------------------------------------------
-LogicalProjectionToProjection::LogicalProjectionToProjection() {
-  type_ = RuleType::PROJECTION_TO_PHYSOCAL;
+LogicalProjectionToProjection::LogicalProjectionToProjection()
+{
+  type_          = RuleType::PROJECTION_TO_PHYSOCAL;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALPROJECTION));
-  auto child = new Pattern(OpType::LEAF);
+  auto child     = new Pattern(OpType::LEAF);
   match_pattern_->add_child(child);
 }
 
-void LogicalProjectionToProjection::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const {
-  auto project_oper = dynamic_cast<ProjectLogicalOperator*>(input);
-  vector<unique_ptr<LogicalOperator>> &child_opers = project_oper->children();
+void LogicalProjectionToProjection::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
+{
+  auto                                 project_oper = dynamic_cast<ProjectLogicalOperator *>(input);
+  vector<unique_ptr<LogicalOperator>> &child_opers  = project_oper->children();
   ASSERT(child_opers.size() == 1, "only one child is supported for now");
 
   unique_ptr<PhysicalOperator> child_phy_oper;
@@ -85,20 +89,20 @@ void LogicalProjectionToProjection::transform(OperatorNode* input,
 // -------------------------------------------------------------------------------------------------
 // PhysicalInsert
 // -------------------------------------------------------------------------------------------------
-LogicalInsertToInsert::LogicalInsertToInsert() {
-  type_ = RuleType::INSERT_TO_PHYSICAL;
+LogicalInsertToInsert::LogicalInsertToInsert()
+{
+  type_          = RuleType::INSERT_TO_PHYSICAL;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALINSERT));
 }
 
+void LogicalInsertToInsert::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
+{
+  InsertLogicalOperator *insert_oper = dynamic_cast<InsertLogicalOperator *>(input);
 
-void LogicalInsertToInsert::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const {
-  InsertLogicalOperator* insert_oper = dynamic_cast<InsertLogicalOperator*>(input);
-
-  Table                  *table           = insert_oper->table();
-  vector<Value>          &values          = insert_oper->values();
-  auto insert_phy_oper = make_unique<InsertPhysicalOperator>(table, std::move(values));
+  Table         *table           = insert_oper->table();
+  vector<Value> &values          = insert_oper->values();
+  auto           insert_phy_oper = make_unique<InsertPhysicalOperator>(table, std::move(values));
 
   transformed->emplace_back(std::move(insert_phy_oper));
 }
@@ -108,17 +112,16 @@ void LogicalInsertToInsert::transform(OperatorNode* input,
 // -------------------------------------------------------------------------------------------------
 LogicalExplainToExplain::LogicalExplainToExplain()
 {
-  type_ = RuleType::EXPLAIN_TO_PHYSICAL;
+  type_          = RuleType::EXPLAIN_TO_PHYSICAL;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALEXPLAIN));
-  auto child = new Pattern(OpType::LEAF);
+  auto child     = new Pattern(OpType::LEAF);
   match_pattern_->add_child(child);
 }
 
-void LogicalExplainToExplain::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const
+void LogicalExplainToExplain::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
 {
-  auto explain_oper = dynamic_cast<ExplainLogicalOperator*>(input);
+  auto                         explain_oper = dynamic_cast<ExplainLogicalOperator *>(input);
   unique_ptr<PhysicalOperator> explain_physical_oper(new ExplainPhysicalOperator());
   for (auto &child : explain_oper->children()) {
     explain_physical_oper->add_general_child(child.get());
@@ -132,15 +135,14 @@ void LogicalExplainToExplain::transform(OperatorNode* input,
 // -------------------------------------------------------------------------------------------------
 LogicalCalcToCalc::LogicalCalcToCalc()
 {
-  type_ = RuleType::CALC_TO_PHYSICAL;
+  type_          = RuleType::CALC_TO_PHYSICAL;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALCALCULATE));
 }
 
-void LogicalCalcToCalc::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const
+void LogicalCalcToCalc::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
 {
-  auto calc_oper = dynamic_cast<CalcLogicalOperator*>(input);
+  auto                             calc_oper = dynamic_cast<CalcLogicalOperator *>(input);
   unique_ptr<CalcPhysicalOperator> calc_phys_oper(new CalcPhysicalOperator(std::move(calc_oper->expressions())));
 
   transformed->emplace_back(std::move(calc_phys_oper));
@@ -151,17 +153,16 @@ void LogicalCalcToCalc::transform(OperatorNode* input,
 // -------------------------------------------------------------------------------------------------
 LogicalDeleteToDelete::LogicalDeleteToDelete()
 {
-  type_ = RuleType::DELETE_TO_PHYSICAL;
+  type_          = RuleType::DELETE_TO_PHYSICAL;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALDELETE));
-  auto child = new Pattern(OpType::LEAF);
+  auto child     = new Pattern(OpType::LEAF);
   match_pattern_->add_child(child);
 }
 
-void LogicalDeleteToDelete::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const
+void LogicalDeleteToDelete::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
 {
-  auto delete_oper = dynamic_cast<DeleteLogicalOperator*>(input);
+  auto delete_oper = dynamic_cast<DeleteLogicalOperator *>(input);
 
   auto delete_phys_oper = unique_ptr<PhysicalOperator>(new DeletePhysicalOperator(delete_oper->table()));
   for (auto &child : delete_oper->children()) {
@@ -176,23 +177,23 @@ void LogicalDeleteToDelete::transform(OperatorNode* input,
 // -------------------------------------------------------------------------------------------------
 LogicalPredicateToPredicate::LogicalPredicateToPredicate()
 {
-  type_ = RuleType::PREDICATE_TO_PHYSICAL;
+  type_          = RuleType::PREDICATE_TO_PHYSICAL;
   match_pattern_ = unique_ptr<Pattern>(new Pattern(OpType::LOGICALFILTER));
-  auto child = new Pattern(OpType::LEAF);
+  auto child     = new Pattern(OpType::LEAF);
   match_pattern_->add_child(child);
 }
 
-void LogicalPredicateToPredicate::transform(OperatorNode* input,
-                         std::vector<std::unique_ptr<OperatorNode>> *transformed,
-                         OptimizerContext *context) const
+void LogicalPredicateToPredicate::transform(
+    OperatorNode *input, std::vector<std::unique_ptr<OperatorNode>> *transformed, OptimizerContext *context) const
 {
-  auto predicate_oper = dynamic_cast<PredicateLogicalOperator*>(input);
+  auto predicate_oper = dynamic_cast<PredicateLogicalOperator *>(input);
 
   vector<unique_ptr<Expression>> &expressions = predicate_oper->expressions();
   ASSERT(expressions.size() == 1, "predicate logical operator's children should be 1");
 
-  unique_ptr<Expression> expression = std::move(expressions.front());
-  unique_ptr<PhysicalOperator> oper = unique_ptr<PhysicalOperator>(new PredicatePhysicalOperator(std::move(expression)));
+  unique_ptr<Expression>       expression = std::move(expressions.front());
+  unique_ptr<PhysicalOperator> oper =
+      unique_ptr<PhysicalOperator>(new PredicatePhysicalOperator(std::move(expression)));
   for (auto &child : predicate_oper->children()) {
     oper->add_general_child(child.get());
   }
@@ -210,7 +211,6 @@ void LogicalPredicateToPredicate::transform(OperatorNode* input,
 //   match_pattern_->add_child(child);
 // }
 
-
 // void LogicalGroupByToAggregation::transform(OperatorNode* input,
 //                          std::vector<std::unique_ptr<OperatorNode>> *transformed,
 //                          OptimizerContext *context) const
@@ -230,7 +230,6 @@ void LogicalPredicateToPredicate::transform(OperatorNode* input,
 //   transformed->emplace_back(std::move(groupby_phys_oper));
 // }
 
-
 // -------------------------------------------------------------------------------------------------
 // Physical Hash Group By
 // -------------------------------------------------------------------------------------------------
@@ -242,7 +241,6 @@ void LogicalPredicateToPredicate::transform(OperatorNode* input,
 //   match_pattern_->add_child(child);
 // }
 
-
 // void LogicalGroupByToHashGroupBy::transform(OperatorNode* input,
 //                          std::vector<std::unique_ptr<OperatorNode>> *transformed,
 //                          OptimizerContext *context) const
@@ -261,4 +259,5 @@ void LogicalPredicateToPredicate::transform(OperatorNode* input,
 //   }
 
 //   transformed->emplace_back(std::move(groupby_phys_oper));
-// }
\ No newline at end of file
+// }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/implementation_rules.h b/src/observer/sql/optimizer/cascade/implementation_rules.h
index d82182ce6..daac7efda 100644
--- a/src/observer/sql/optimizer/cascade/implementation_rules.h
+++ b/src/observer/sql/optimizer/cascade/implementation_rules.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/cascade/rules.h"
 
+namespace oceanbase {
+
 /**
  * Rule transforms Logical Scan -> Physical Scan
  */
@@ -125,4 +127,5 @@ class LogicalPredicateToPredicate : public Rule
 //   void transform(OperatorNode* input,
 //                          std::vector<std::unique_ptr<OperatorNode>> *transformed,
 //                          OptimizerContext *context) const override;
-// };
\ No newline at end of file
+// };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/memo.cpp b/src/observer/sql/optimizer/cascade/memo.cpp
index 677d34ab6..0119ee974 100644
--- a/src/observer/sql/optimizer/cascade/memo.cpp
+++ b/src/observer/sql/optimizer/cascade/memo.cpp
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/cascade/memo.h"
 
+namespace oceanbase {
+
 GroupExpr *Memo::insert_expression(GroupExpr *gexpr, int target_group)
 {
   gexpr->set_group_id(target_group);
@@ -50,4 +52,5 @@ void Memo::dump() const
   for (const auto &group : groups_) {
     group->dump();
   }
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/memo.h b/src/observer/sql/optimizer/cascade/memo.h
index cef553795..0ddbf5af5 100644
--- a/src/observer/sql/optimizer/cascade/memo.h
+++ b/src/observer/sql/optimizer/cascade/memo.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/group_expr.h"
 #include "sql/optimizer/cascade/group.h"
 
+namespace oceanbase {
+
 const int UNDEFINED_GROUP = -1;
 
 /**
@@ -90,4 +92,5 @@ class Memo
   // 过程中生成的临时物理算子节点的，有些物理算子节点的所有权会转移到外面，有些物理算子的所有权还在memo，需要删除。 用
   // shared_ptr 更加合适，但是改动比较大，先暂时不改了。
   std::unordered_map<OperatorNode *, unique_ptr<OperatorNode>> operator_nodes_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/optimizer.cpp b/src/observer/sql/optimizer/cascade/optimizer.cpp
index dd6b26a68..b6c29857a 100644
--- a/src/observer/sql/optimizer/cascade/optimizer.cpp
+++ b/src/observer/sql/optimizer/cascade/optimizer.cpp
@@ -12,11 +12,13 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/o_group_task.h"
 #include "sql/optimizer/cascade/memo.h"
 
-std::unique_ptr<PhysicalOperator> Optimizer::optimize(OperatorNode* op_tree)
+namespace oceanbase {
+
+std::unique_ptr<PhysicalOperator> Optimizer::optimize(OperatorNode *op_tree)
 {
   // Generate initial operator tree from query tree
-  GroupExpr *gexpr = nullptr;
-  bool insert = context_->record_node_into_group(op_tree, &gexpr);
+  GroupExpr *gexpr  = nullptr;
+  bool       insert = context_->record_node_into_group(op_tree, &gexpr);
   ASSERT(insert && gexpr, "Logical expression tree should insert");
   context_->get_memo().dump();
 
@@ -30,7 +32,7 @@ std::unique_ptr<PhysicalOperator> Optimizer::optimize(OperatorNode* op_tree)
 
 std::unique_ptr<PhysicalOperator> Optimizer::choose_best_plan(int root_group_id)
 {
-  auto &memo = context_->get_memo();
+  auto  &memo       = context_->get_memo();
   Group *root_group = memo.get_group_by_id(root_group_id);
   ASSERT(root_group != nullptr, "Root group should not be null");
 
@@ -42,9 +44,9 @@ std::unique_ptr<PhysicalOperator> Optimizer::choose_best_plan(int root_group_id)
   }
   auto winner_contents = winner->get_op();
   context_->get_memo().release_operator(winner_contents);
-  PhysicalOperator* winner_phys = dynamic_cast<PhysicalOperator*>(winner_contents);
+  PhysicalOperator *winner_phys = dynamic_cast<PhysicalOperator *>(winner_contents);
   LOG_TRACE("winner: %d", winner_phys->type());
-  for (const auto& child : winner->get_child_group_ids()) {
+  for (const auto &child : winner->get_child_group_ids()) {
     winner_phys->add_child(choose_best_plan(child));
   }
 
@@ -70,3 +72,4 @@ void Optimizer::execute_task_stack(PendingTasks *task_stack, int root_group_id,
     delete task;
   }
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/optimizer.h b/src/observer/sql/optimizer/cascade/optimizer.h
index 724d4a9de..c6dd7cf54 100644
--- a/src/observer/sql/optimizer/cascade/optimizer.h
+++ b/src/observer/sql/optimizer/cascade/optimizer.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/physical_operator.h"
 #include "sql/optimizer/cascade/property_set.h"
 
+namespace oceanbase {
+
 /**
  * @brief cascade optimizer
  * TODO: currently, Optimizer is used for CBO optimization. need to unify the optimizer in miniob
@@ -35,4 +37,5 @@ class Optimizer
 
   CostModel                         cost_model_;
   std::unique_ptr<OptimizerContext> context_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/optimizer_context.cpp b/src/observer/sql/optimizer/cascade/optimizer_context.cpp
index 4dce30d85..fbd0fa4b1 100644
--- a/src/observer/sql/optimizer/cascade/optimizer_context.cpp
+++ b/src/observer/sql/optimizer/cascade/optimizer_context.cpp
@@ -12,26 +12,33 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/memo.h"
 #include "sql/optimizer/cascade/rules.h"
 
+namespace oceanbase {
+
 OptimizerContext::OptimizerContext()
-      : memo_(new Memo()), rule_set_(new RuleSet()), cost_model_(), task_pool_(nullptr),
-        cost_upper_bound_(std::numeric_limits<double>::max()) {}
+    : memo_(new Memo()),
+      rule_set_(new RuleSet()),
+      cost_model_(),
+      task_pool_(nullptr),
+      cost_upper_bound_(std::numeric_limits<double>::max())
+{}
 
-OptimizerContext::~OptimizerContext() {
-    if (task_pool_ != nullptr) {
-      delete task_pool_;
-      task_pool_ = nullptr;
-    }
-    if (memo_ != nullptr) {
-      delete memo_;
-      memo_ = nullptr;
-    }
-    if (rule_set_ != nullptr) {
-      delete rule_set_;
-      rule_set_ = nullptr;
-    }
+OptimizerContext::~OptimizerContext()
+{
+  if (task_pool_ != nullptr) {
+    delete task_pool_;
+    task_pool_ = nullptr;
+  }
+  if (memo_ != nullptr) {
+    delete memo_;
+    memo_ = nullptr;
+  }
+  if (rule_set_ != nullptr) {
+    delete rule_set_;
+    rule_set_ = nullptr;
   }
+}
 
-GroupExpr *OptimizerContext::make_group_expression(OperatorNode* node)
+GroupExpr *OptimizerContext::make_group_expression(OperatorNode *node)
 {
   std::vector<int> child_groups;
   for (auto &child : node->get_general_children()) {
@@ -50,21 +57,22 @@ GroupExpr *OptimizerContext::make_group_expression(OperatorNode* node)
   return new GroupExpr(node, std::move(child_groups));
 }
 
-  bool OptimizerContext::record_node_into_group(OperatorNode* node, GroupExpr **gexpr,
-                                    int target_group) {
-    auto new_gexpr = make_group_expression(node);
-    auto ptr = memo_->insert_expression(new_gexpr, target_group);
-    ASSERT(ptr, "Root of expr should not fail insertion");
+bool OptimizerContext::record_node_into_group(OperatorNode *node, GroupExpr **gexpr, int target_group)
+{
+  auto new_gexpr = make_group_expression(node);
+  auto ptr       = memo_->insert_expression(new_gexpr, target_group);
+  ASSERT(ptr, "Root of expr should not fail insertion");
 
-    (*gexpr) = ptr;
-    return (ptr == new_gexpr);
-  }
+  (*gexpr) = ptr;
+  return (ptr == new_gexpr);
+}
 
-  Memo &OptimizerContext::get_memo() { return *memo_; }
+Memo &OptimizerContext::get_memo() { return *memo_; }
 
-  RuleSet &OptimizerContext::get_rule_set() { return *rule_set_; }
+RuleSet &OptimizerContext::get_rule_set() { return *rule_set_; }
 
-  void OptimizerContext::record_operator_node_in_memo(unique_ptr<OperatorNode>&& node)
-  {
-    memo_->record_operator(std::move(node));
-  }
\ No newline at end of file
+void OptimizerContext::record_operator_node_in_memo(unique_ptr<OperatorNode> &&node)
+{
+  memo_->record_operator(std::move(node));
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/optimizer_context.h b/src/observer/sql/optimizer/cascade/optimizer_context.h
index a77fc8162..ae81af119 100644
--- a/src/observer/sql/optimizer/cascade/optimizer_context.h
+++ b/src/observer/sql/optimizer/cascade/optimizer_context.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/operator_node.h"
 #include "sql/optimizer/cascade/property_set.h"
 
+namespace oceanbase {
+
 class Memo;
 class RuleSet;
 /**
@@ -62,4 +64,5 @@ class OptimizerContext
   CostModel     cost_model_;
   PendingTasks *task_pool_;
   double        cost_upper_bound_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/pattern.h b/src/observer/sql/optimizer/cascade/pattern.h
index 204bac204..414c2d5d4 100644
--- a/src/observer/sql/optimizer/cascade/pattern.h
+++ b/src/observer/sql/optimizer/cascade/pattern.h
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "common/lang/memory.h"
 
+namespace oceanbase {
+
 class Pattern
 {
 public:
@@ -32,4 +34,5 @@ class Pattern
   OpType type_;
 
   vector<unique_ptr<Pattern>> children_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/pending_tasks.h b/src/observer/sql/optimizer/cascade/pending_tasks.h
index 1e6494d82..8783a1dad 100644
--- a/src/observer/sql/optimizer/cascade/pending_tasks.h
+++ b/src/observer/sql/optimizer/cascade/pending_tasks.h
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "sql/optimizer/cascade/tasks/cascade_task.h"
 
+namespace oceanbase {
+
 /**
  * @brief This collection of undone cascade tasks is currently stored as a stack.
  */
@@ -50,4 +52,5 @@ class PendingTasks
    * Stack for tracking tasks
    */
   std::stack<CascadeTask *> task_stack_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/property.h b/src/observer/sql/optimizer/cascade/property.h
index 965e034db..692f78340 100644
--- a/src/observer/sql/optimizer/cascade/property.h
+++ b/src/observer/sql/optimizer/cascade/property.h
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 class Property
 {};
 
@@ -27,4 +29,5 @@ class LogicalProperty
 
 private:
   int card_ = 0;  /// cardinality
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/property_set.h b/src/observer/sql/optimizer/cascade/property_set.h
index b6808d9fe..9e4479028 100644
--- a/src/observer/sql/optimizer/cascade/property_set.h
+++ b/src/observer/sql/optimizer/cascade/property_set.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/cascade/property.h"
 
+namespace oceanbase {
+
 class PropertySet;
 struct PropSetPtrHash
 {
@@ -40,4 +42,5 @@ class PropertySet
 
 private:
   std::vector<Property *> properties_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/rules.cpp b/src/observer/sql/optimizer/cascade/rules.cpp
index c78fbf596..2b701465c 100644
--- a/src/observer/sql/optimizer/cascade/rules.cpp
+++ b/src/observer/sql/optimizer/cascade/rules.cpp
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/implementation_rules.h"
 #include "sql/optimizer/cascade/group_expr.h"
 
+namespace oceanbase {
+
 RuleSet::RuleSet()
 {
   add_rule(RuleSetName::PHYSICAL_IMPLEMENTATION, new LogicalProjectionToProjection());
@@ -21,4 +23,5 @@ RuleSet::RuleSet()
   add_rule(RuleSetName::PHYSICAL_IMPLEMENTATION, new LogicalCalcToCalc());
   add_rule(RuleSetName::PHYSICAL_IMPLEMENTATION, new LogicalDeleteToDelete());
   add_rule(RuleSetName::PHYSICAL_IMPLEMENTATION, new LogicalPredicateToPredicate());
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/rules.h b/src/observer/sql/optimizer/cascade/rules.h
index b60547a31..26a0dc53d 100644
--- a/src/observer/sql/optimizer/cascade/rules.h
+++ b/src/observer/sql/optimizer/cascade/rules.h
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/optimizer_context.h"
 #include "sql/optimizer/cascade/pattern.h"
 
+namespace oceanbase {
+
 /**
  * @brief: Enum defining the types of rules
  */
@@ -193,4 +195,5 @@ class RuleSet
    * TODO: use unique_ptr
    */
   std::unordered_map<uint32_t, std::vector<Rule *>> rules_map_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.cpp b/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.cpp
index d40c0e570..61c4031f8 100644
--- a/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.cpp
+++ b/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/rules.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 void ApplyRule::perform()
 {
   LOG_TRACE("ApplyRule::perform() for rule: {%d}", rule_->get_rule_idx());
@@ -22,7 +24,7 @@ void ApplyRule::perform()
     return;
   }
   // TODO: expr binding, currently group_expr_->get_op() is enough
-  OperatorNode* before = group_expr_->get_op();
+  OperatorNode *before = group_expr_->get_op();
 
   // TODO: check condition
 
@@ -30,7 +32,7 @@ void ApplyRule::perform()
   rule_->transform(before, &after, context_);
   for (const auto &new_expr : after) {
     GroupExpr *new_gexpr = nullptr;
-    auto g_id = group_expr_->get_group_id();
+    auto       g_id      = group_expr_->get_group_id();
     if (context_->record_node_into_group(new_expr.get(), &new_gexpr, g_id)) {
       if (new_gexpr->get_op()->is_logical()) {
         // further optimize new expr
@@ -44,11 +46,12 @@ void ApplyRule::perform()
       new_gexpr->dump();
     }
   }
-  
+
   // TODO: FIXME, better way for record memory allocation
   for (size_t i = 0; i < after.size(); i++) {
     context_->record_operator_node_in_memo(std::move(after[i]));
   }
 
   group_expr_->set_rule_explored(rule_);
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.h b/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.h
index 124bf2974..8f2fef4f2 100644
--- a/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.h
+++ b/src/observer/sql/optimizer/cascade/tasks/apply_rule_task.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/cascade_task.h"
 #include "sql/optimizer/cascade/rules.h"
 
+namespace oceanbase {
+
 /**
  * @brief ApplyRule task
  */
@@ -28,4 +30,5 @@ class ApplyRule : public CascadeTask
 private:
   GroupExpr *group_expr_;
   Rule      *rule_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/cascade_task.cpp b/src/observer/sql/optimizer/cascade/tasks/cascade_task.cpp
index aa304930a..ca4dfbfd5 100644
--- a/src/observer/sql/optimizer/cascade/tasks/cascade_task.cpp
+++ b/src/observer/sql/optimizer/cascade/tasks/cascade_task.cpp
@@ -14,8 +14,11 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/rules.h"
 #include "sql/optimizer/cascade/memo.h"
 
-Memo &CascadeTask::get_memo() const {return context_->get_memo(); }
+namespace oceanbase {
+
+Memo &CascadeTask::get_memo() const { return context_->get_memo(); }
 
 RuleSet &CascadeTask::get_rule_set() const { return context_->get_rule_set(); }
 
-void CascadeTask::push_task(CascadeTask *task) { context_->push_task(task); }
\ No newline at end of file
+void CascadeTask::push_task(CascadeTask *task) { context_->push_task(task); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/cascade_task.h b/src/observer/sql/optimizer/cascade/tasks/cascade_task.h
index da7987f5b..71845145c 100644
--- a/src/observer/sql/optimizer/cascade/tasks/cascade_task.h
+++ b/src/observer/sql/optimizer/cascade/tasks/cascade_task.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/lang/vector.h"
 
+namespace oceanbase {
+
 class Rule;
 class GroupExpr;
 class RuleSet;
@@ -46,4 +48,5 @@ class CascadeTask
 protected:
   CascadeTaskType   type_;
   OptimizerContext *context_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/e_group_task.cpp b/src/observer/sql/optimizer/cascade/tasks/e_group_task.cpp
index 426f2e904..f10c08cb3 100644
--- a/src/observer/sql/optimizer/cascade/tasks/e_group_task.cpp
+++ b/src/observer/sql/optimizer/cascade/tasks/e_group_task.cpp
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/o_expr_task.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 void ExploreGroup::perform()
 {
   LOG_TRACE("ExploreGroup::perform() ");
@@ -24,4 +26,5 @@ void ExploreGroup::perform()
   }
 
   group_->set_explored();
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/e_group_task.h b/src/observer/sql/optimizer/cascade/tasks/e_group_task.h
index f1534127f..89eee3a1c 100644
--- a/src/observer/sql/optimizer/cascade/tasks/e_group_task.h
+++ b/src/observer/sql/optimizer/cascade/tasks/e_group_task.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/cascade_task.h"
 #include "sql/optimizer/cascade/group.h"
 
+namespace oceanbase {
+
 /**
  * @brief ExploreGroup
  */
@@ -27,4 +29,5 @@ class ExploreGroup : public CascadeTask
 
 private:
   Group *group_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/o_expr_task.cpp b/src/observer/sql/optimizer/cascade/tasks/o_expr_task.cpp
index 8e45af9e2..4445ef193 100644
--- a/src/observer/sql/optimizer/cascade/tasks/o_expr_task.cpp
+++ b/src/observer/sql/optimizer/cascade/tasks/o_expr_task.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include <algorithm>
 
+namespace oceanbase {
+
 void OptimizeExpression::perform()
 {
   std::vector<RuleWithPromise> valid_rules;
@@ -59,3 +61,4 @@ void OptimizeExpression::perform()
     }
   }
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/o_expr_task.h b/src/observer/sql/optimizer/cascade/tasks/o_expr_task.h
index afd71029b..0ec6805a2 100644
--- a/src/observer/sql/optimizer/cascade/tasks/o_expr_task.h
+++ b/src/observer/sql/optimizer/cascade/tasks/o_expr_task.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/cascade/tasks/cascade_task.h"
 
+namespace oceanbase {
+
 /**
  * OptimizeExpression
  */
@@ -26,4 +28,5 @@ class OptimizeExpression : public CascadeTask
 
 private:
   GroupExpr *group_expr_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/o_group_task.cpp b/src/observer/sql/optimizer/cascade/tasks/o_group_task.cpp
index 47f06bdcc..61fb4f14b 100644
--- a/src/observer/sql/optimizer/cascade/tasks/o_group_task.cpp
+++ b/src/observer/sql/optimizer/cascade/tasks/o_group_task.cpp
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/o_expr_task.h"
 #include "sql/optimizer/cascade/optimizer_context.h"
 
+namespace oceanbase {
+
 void OptimizeGroup::perform()
 {
   LOG_TRACE("OptimizeGroup::perform() group %d", group_->get_id());
@@ -35,4 +37,5 @@ void OptimizeGroup::perform()
   }
 
   group_->set_explored();
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/o_group_task.h b/src/observer/sql/optimizer/cascade/tasks/o_group_task.h
index afad210e0..405a3e14b 100644
--- a/src/observer/sql/optimizer/cascade/tasks/o_group_task.h
+++ b/src/observer/sql/optimizer/cascade/tasks/o_group_task.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/cascade_task.h"
 #include "sql/optimizer/cascade/group.h"
 
+namespace oceanbase {
+
 /**
  * @brief: OptimizeGroup, find the best plan for a group
  */
@@ -27,4 +29,5 @@ class OptimizeGroup : public CascadeTask
 
 private:
   Group *group_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/o_input_task.cpp b/src/observer/sql/optimizer/cascade/tasks/o_input_task.cpp
index 9ad9b7c7e..c14b3dda9 100644
--- a/src/observer/sql/optimizer/cascade/tasks/o_input_task.cpp
+++ b/src/observer/sql/optimizer/cascade/tasks/o_input_task.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/memo.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 void OptimizeInputs::perform()
 {
   LOG_TRACE("OptimizeInputs::perform()");
@@ -23,19 +25,18 @@ void OptimizeInputs::perform()
 
     cur_child_idx_ = 0;
     // only calculate once for current group expr
-    cur_total_cost_ += context_->get_cost_model()->calculate_cost(
-          &context_->get_memo(), group_expr_);
+    cur_total_cost_ += context_->get_cost_model()->calculate_cost(&context_->get_memo(), group_expr_);
   }
   for (; cur_child_idx_ < static_cast<int>(group_expr_->get_children_groups_size()); cur_child_idx_++) {
-    auto child_group =
-        context_->get_memo().get_group_by_id(group_expr_->get_child_group_id(cur_child_idx_));
+    auto child_group = context_->get_memo().get_group_by_id(group_expr_->get_child_group_id(cur_child_idx_));
 
     // check whether the child group is already optimized
     auto child_best_expr = child_group->get_winner();
     if (child_best_expr != nullptr) {
       cur_total_cost_ += child_best_expr->get_cost();
       LOG_INFO("cur_total_cost_ = %f", cur_total_cost_);
-      if (cur_total_cost_ > context_->get_cost_upper_bound()) break;
+      if (cur_total_cost_ > context_->get_cost_upper_bound())
+        break;
     } else if (prev_child_idx_ != cur_child_idx_) {  // we haven't optimized child group
       prev_child_idx_ = cur_child_idx_;
       push_task(new OptimizeInputs(this));
@@ -44,10 +45,11 @@ void OptimizeInputs::perform()
     }
   }
 
-    if (cur_child_idx_ == static_cast<int>(group_expr_->get_children_groups_size())) {
-      group_expr_->set_local_cost(cur_total_cost_);
+  if (cur_child_idx_ == static_cast<int>(group_expr_->get_children_groups_size())) {
+    group_expr_->set_local_cost(cur_total_cost_);
 
-      auto cur_group = get_memo().get_group_by_id(group_expr_->get_group_id());
-      cur_group->set_expr_cost(group_expr_, cur_total_cost_);
-    }
-}
\ No newline at end of file
+    auto cur_group = get_memo().get_group_by_id(group_expr_->get_group_id());
+    cur_group->set_expr_cost(group_expr_, cur_total_cost_);
+  }
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/cascade/tasks/o_input_task.h b/src/observer/sql/optimizer/cascade/tasks/o_input_task.h
index 0c3100bad..a67ba0b1c 100644
--- a/src/observer/sql/optimizer/cascade/tasks/o_input_task.h
+++ b/src/observer/sql/optimizer/cascade/tasks/o_input_task.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/cascade/tasks/cascade_task.h"
 #include "sql/optimizer/cascade/property_set.h"
 
+namespace oceanbase {
+
 /**
  * OptimizeInputs
  */
@@ -48,4 +50,5 @@ class OptimizeInputs : public CascadeTask
    * keep track of the previous optimized input idx
    */
   int prev_child_idx_ = -1;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/comparison_simplification_rule.cpp b/src/observer/sql/optimizer/comparison_simplification_rule.cpp
index 99a7655ce..9c0977a9f 100644
--- a/src/observer/sql/optimizer/comparison_simplification_rule.cpp
+++ b/src/observer/sql/optimizer/comparison_simplification_rule.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "sql/expr/expression.h"
 
+namespace oceanbase {
+
 RC ComparisonSimplificationRule::rewrite(unique_ptr<Expression> &expr, bool &change_made)
 {
   RC rc = RC::SUCCESS;
@@ -36,3 +38,4 @@ RC ComparisonSimplificationRule::rewrite(unique_ptr<Expression> &expr, bool &cha
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/comparison_simplification_rule.h b/src/observer/sql/optimizer/comparison_simplification_rule.h
index f46e70d6e..85f4ca1f5 100644
--- a/src/observer/sql/optimizer/comparison_simplification_rule.h
+++ b/src/observer/sql/optimizer/comparison_simplification_rule.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "sql/optimizer/rewrite_rule.h"
 
+namespace oceanbase {
+
 class LogicalOperator;
 
 /**
@@ -35,3 +37,4 @@ class ComparisonSimplificationRule : public ExpressionRewriteRule
 
 private:
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/conjunction_simplification_rule.cpp b/src/observer/sql/optimizer/conjunction_simplification_rule.cpp
index 5ba4e4148..450eaf5eb 100644
--- a/src/observer/sql/optimizer/conjunction_simplification_rule.cpp
+++ b/src/observer/sql/optimizer/conjunction_simplification_rule.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "sql/expr/expression.h"
 
+namespace oceanbase {
+
 RC try_to_get_bool_constant(unique_ptr<Expression> &expr, bool &constant_value)
 {
   if (expr->type() == ExprType::VALUE && expr->value_type() == AttrType::BOOLEANS) {
@@ -32,17 +34,17 @@ RC ConjunctionSimplificationRule::rewrite(unique_ptr<Expression> &expr, bool &ch
     return rc;
   }
 
-  change_made                                                = false;
-  auto                                      conjunction_expr = static_cast<ConjunctionExpr *>(expr.get());
+  change_made           = false;
+  auto conjunction_expr = static_cast<ConjunctionExpr *>(expr.get());
 
-  vector<unique_ptr<Expression>> &child_exprs      = conjunction_expr->children();
+  vector<unique_ptr<Expression>> &child_exprs = conjunction_expr->children();
 
   // 先看看有没有能够直接去掉的表达式。比如AND时恒为true的表达式可以删除
   // 或者是否可以直接计算出当前表达式的值。比如AND时，如果有一个表达式为false，那么整个表达式就是false
   for (auto iter = child_exprs.begin(); iter != child_exprs.end();) {
     bool constant_value = false;
 
-    rc                  = try_to_get_bool_constant(*iter, constant_value);
+    rc = try_to_get_bool_constant(*iter, constant_value);
     if (rc != RC::SUCCESS) {
       rc = RC::SUCCESS;
       ++iter;
@@ -83,3 +85,4 @@ RC ConjunctionSimplificationRule::rewrite(unique_ptr<Expression> &expr, bool &ch
 
   return rc;
 }
+}  // namespace oceanbase
diff --git a/src/observer/sql/optimizer/conjunction_simplification_rule.h b/src/observer/sql/optimizer/conjunction_simplification_rule.h
index c855f0141..104a82246 100644
--- a/src/observer/sql/optimizer/conjunction_simplification_rule.h
+++ b/src/observer/sql/optimizer/conjunction_simplification_rule.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/rewrite_rule.h"
 
+namespace oceanbase {
+
 class LogicalOperator;
 
 /**
@@ -33,3 +35,4 @@ class ConjunctionSimplificationRule : public ExpressionRewriteRule
 
 private:
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/expression_rewriter.cpp b/src/observer/sql/optimizer/expression_rewriter.cpp
index b0c6d2455..3b3cd2d66 100644
--- a/src/observer/sql/optimizer/expression_rewriter.cpp
+++ b/src/observer/sql/optimizer/expression_rewriter.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 ExpressionRewriter::ExpressionRewriter()
 {
   expr_rewrite_rules_.emplace_back(new ComparisonSimplificationRule);
@@ -69,7 +71,7 @@ RC ExpressionRewriter::rewrite_expression(unique_ptr<Expression> &expr, bool &ch
   for (unique_ptr<ExpressionRewriteRule> &rule : expr_rewrite_rules_) {
     bool sub_change_made = false;
 
-    rc                   = rule->rewrite(expr, sub_change_made);
+    rc = rule->rewrite(expr, sub_change_made);
     if (sub_change_made && !change_made) {
       change_made = true;
     }
@@ -91,25 +93,25 @@ RC ExpressionRewriter::rewrite_expression(unique_ptr<Expression> &expr, bool &ch
     case ExprType::CAST: {
       unique_ptr<Expression> &child_expr = (static_cast<CastExpr *>(expr.get()))->child();
 
-      rc                                      = rewrite_expression(child_expr, change_made);
+      rc = rewrite_expression(child_expr, change_made);
     } break;
 
     case ExprType::COMPARISON: {
-      auto                         comparison_expr = static_cast<ComparisonExpr *>(expr.get());
+      auto comparison_expr = static_cast<ComparisonExpr *>(expr.get());
 
-      unique_ptr<Expression> &left_expr       = comparison_expr->left();
-      unique_ptr<Expression> &right_expr      = comparison_expr->right();
+      unique_ptr<Expression> &left_expr  = comparison_expr->left();
+      unique_ptr<Expression> &right_expr = comparison_expr->right();
 
       bool left_change_made = false;
 
-      rc                    = rewrite_expression(left_expr, left_change_made);
+      rc = rewrite_expression(left_expr, left_change_made);
       if (rc != RC::SUCCESS) {
         return rc;
       }
 
       bool right_change_made = false;
 
-      rc                     = rewrite_expression(right_expr, right_change_made);
+      rc = rewrite_expression(right_expr, right_change_made);
       if (rc != RC::SUCCESS) {
         return rc;
       }
@@ -120,13 +122,13 @@ RC ExpressionRewriter::rewrite_expression(unique_ptr<Expression> &expr, bool &ch
     } break;
 
     case ExprType::CONJUNCTION: {
-      auto                                      conjunction_expr = static_cast<ConjunctionExpr *>(expr.get());
+      auto conjunction_expr = static_cast<ConjunctionExpr *>(expr.get());
 
-      vector<unique_ptr<Expression>> &children         = conjunction_expr->children();
+      vector<unique_ptr<Expression>> &children = conjunction_expr->children();
       for (unique_ptr<Expression> &child_expr : children) {
         bool sub_change_made = false;
 
-        rc                   = rewrite_expression(child_expr, sub_change_made);
+        rc = rewrite_expression(child_expr, sub_change_made);
         if (rc != RC::SUCCESS) {
 
           LOG_WARN("failed to rewriter conjunction sub expression. rc=%s", strrc(rc));
@@ -145,3 +147,4 @@ RC ExpressionRewriter::rewrite_expression(unique_ptr<Expression> &expr, bool &ch
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/expression_rewriter.h b/src/observer/sql/optimizer/expression_rewriter.h
index 3376b1db8..a59c0be60 100644
--- a/src/observer/sql/optimizer/expression_rewriter.h
+++ b/src/observer/sql/optimizer/expression_rewriter.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/logical_operator.h"
 #include "sql/optimizer/rewrite_rule.h"
 
+namespace oceanbase {
+
 class ExpressionRewriter : public RewriteRule
 {
 public:
@@ -34,3 +36,4 @@ class ExpressionRewriter : public RewriteRule
 private:
   vector<unique_ptr<ExpressionRewriteRule>> expr_rewrite_rules_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/logical_plan_generator.cpp b/src/observer/sql/optimizer/logical_plan_generator.cpp
index f9da53f3a..40fe3a0c6 100644
--- a/src/observer/sql/optimizer/logical_plan_generator.cpp
+++ b/src/observer/sql/optimizer/logical_plan_generator.cpp
@@ -40,6 +40,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 RC LogicalPlanGenerator::create(Stmt *stmt, unique_ptr<LogicalOperator> &logical_operator)
 {
   RC rc = RC::SUCCESS;
@@ -114,7 +116,6 @@ RC LogicalPlanGenerator::create_plan(SelectStmt *select_stmt, unique_ptr<Logical
     }
   }
 
-
   if (predicate_oper) {
     if (*last_oper) {
       predicate_oper->add_child(std::move(*last_oper));
@@ -138,7 +139,8 @@ RC LogicalPlanGenerator::create_plan(SelectStmt *select_stmt, unique_ptr<Logical
     last_oper = &group_by_oper;
   }
 
-  unique_ptr<LogicalOperator> project_oper = make_unique<ProjectLogicalOperator>(std::move(select_stmt->query_expressions()));
+  unique_ptr<LogicalOperator> project_oper =
+      make_unique<ProjectLogicalOperator>(std::move(select_stmt->query_expressions()));
   if (*last_oper) {
     project_oper->add_child(std::move(*last_oper));
   }
@@ -151,7 +153,7 @@ RC LogicalPlanGenerator::create_plan(SelectStmt *select_stmt, unique_ptr<Logical
 
 RC LogicalPlanGenerator::create_plan(FilterStmt *filter_stmt, unique_ptr<LogicalOperator> &logical_operator)
 {
-  RC                                  rc = RC::SUCCESS;
+  RC                             rc = RC::SUCCESS;
   vector<unique_ptr<Expression>> cmp_exprs;
   const vector<FilterUnit *>    &filter_units = filter_stmt->filter_units();
   for (const FilterUnit *filter_unit : filter_units) {
@@ -171,11 +173,10 @@ RC LogicalPlanGenerator::create_plan(FilterStmt *filter_stmt, unique_ptr<Logical
       auto right_to_left_cost = implicit_cast_cost(right->value_type(), left->value_type());
       if (left_to_right_cost <= right_to_left_cost && left_to_right_cost != INT32_MAX) {
         ExprType left_type = left->type();
-        auto cast_expr = make_unique<CastExpr>(std::move(left), right->value_type());
+        auto     cast_expr = make_unique<CastExpr>(std::move(left), right->value_type());
         if (left_type == ExprType::VALUE) {
           Value left_val;
-          if (OB_FAIL(rc = cast_expr->try_get_value(left_val)))
-          {
+          if (OB_FAIL(rc = cast_expr->try_get_value(left_val))) {
             LOG_WARN("failed to get value from left child", strrc(rc));
             return rc;
           }
@@ -185,11 +186,10 @@ RC LogicalPlanGenerator::create_plan(FilterStmt *filter_stmt, unique_ptr<Logical
         }
       } else if (right_to_left_cost < left_to_right_cost && right_to_left_cost != INT32_MAX) {
         ExprType right_type = right->type();
-        auto cast_expr = make_unique<CastExpr>(std::move(right), left->value_type());
+        auto     cast_expr  = make_unique<CastExpr>(std::move(right), left->value_type());
         if (right_type == ExprType::VALUE) {
           Value right_val;
-          if (OB_FAIL(rc = cast_expr->try_get_value(right_val)))
-          {
+          if (OB_FAIL(rc = cast_expr->try_get_value(right_val))) {
             LOG_WARN("failed to get value from right child", strrc(rc));
             return rc;
           }
@@ -282,10 +282,10 @@ RC LogicalPlanGenerator::create_plan(ExplainStmt *explain_stmt, unique_ptr<Logic
 
 RC LogicalPlanGenerator::create_group_by_plan(SelectStmt *select_stmt, unique_ptr<LogicalOperator> &logical_operator)
 {
-  vector<unique_ptr<Expression>> &group_by_expressions = select_stmt->group_by();
-  vector<Expression *> aggregate_expressions;
-  vector<unique_ptr<Expression>> &query_expressions = select_stmt->query_expressions();
-  function<RC(unique_ptr<Expression>&)> collector = [&](unique_ptr<Expression> &expr) -> RC {
+  vector<unique_ptr<Expression>>        &group_by_expressions = select_stmt->group_by();
+  vector<Expression *>                   aggregate_expressions;
+  vector<unique_ptr<Expression>>        &query_expressions = select_stmt->query_expressions();
+  function<RC(unique_ptr<Expression> &)> collector         = [&](unique_ptr<Expression> &expr) -> RC {
     RC rc = RC::SUCCESS;
     if (expr->type() == ExprType::AGGREGATION) {
       expr->set_pos(aggregate_expressions.size() + group_by_expressions.size());
@@ -295,7 +295,7 @@ RC LogicalPlanGenerator::create_group_by_plan(SelectStmt *select_stmt, unique_pt
     return rc;
   };
 
-  function<RC(unique_ptr<Expression>&)> bind_group_by_expr = [&](unique_ptr<Expression> &expr) -> RC {
+  function<RC(unique_ptr<Expression> &)> bind_group_by_expr = [&](unique_ptr<Expression> &expr) -> RC {
     RC rc = RC::SUCCESS;
     for (size_t i = 0; i < group_by_expressions.size(); i++) {
       auto &group_by = group_by_expressions[i];
@@ -311,8 +311,8 @@ RC LogicalPlanGenerator::create_group_by_plan(SelectStmt *select_stmt, unique_pt
     return rc;
   };
 
- bool found_unbound_column = false;
-  function<RC(unique_ptr<Expression>&)> find_unbound_column = [&](unique_ptr<Expression> &expr) -> RC {
+  bool                                   found_unbound_column = false;
+  function<RC(unique_ptr<Expression> &)> find_unbound_column  = [&](unique_ptr<Expression> &expr) -> RC {
     RC rc = RC::SUCCESS;
     if (expr->type() == ExprType::AGGREGATION) {
       // do nothing
@@ -320,12 +320,11 @@ RC LogicalPlanGenerator::create_group_by_plan(SelectStmt *select_stmt, unique_pt
       // do nothing
     } else if (expr->type() == ExprType::FIELD) {
       found_unbound_column = true;
-    }else {
+    } else {
       rc = ExpressionIterator::iterate_child_expr(*expr, find_unbound_column);
     }
     return rc;
   };
-  
 
   for (unique_ptr<Expression> &expression : query_expressions) {
     bind_group_by_expr(expression);
@@ -352,8 +351,9 @@ RC LogicalPlanGenerator::create_group_by_plan(SelectStmt *select_stmt, unique_pt
 
   // 如果只需要聚合，但是没有group by 语句，需要生成一个空的group by 语句
 
-  auto group_by_oper = make_unique<GroupByLogicalOperator>(std::move(group_by_expressions),
-                                                           std::move(aggregate_expressions));
+  auto group_by_oper =
+      make_unique<GroupByLogicalOperator>(std::move(group_by_expressions), std::move(aggregate_expressions));
   logical_operator = std::move(group_by_oper);
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/logical_plan_generator.h b/src/observer/sql/optimizer/logical_plan_generator.h
index e0707deff..20746ba1b 100644
--- a/src/observer/sql/optimizer/logical_plan_generator.h
+++ b/src/observer/sql/optimizer/logical_plan_generator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/type/attr_type.h"
 
+namespace oceanbase {
+
 class Stmt;
 class CalcStmt;
 class SelectStmt;
@@ -47,3 +49,4 @@ class LogicalPlanGenerator
 
   int implicit_cast_cost(AttrType from, AttrType to);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/optimize_stage.cpp b/src/observer/sql/optimizer/optimize_stage.cpp
index a0560541f..bd6207827 100644
--- a/src/observer/sql/optimizer/optimize_stage.cpp
+++ b/src/observer/sql/optimizer/optimize_stage.cpp
@@ -30,6 +30,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 RC OptimizeStage::handle_request(SQLStageEvent *sql_event)
 {
   unique_ptr<LogicalOperator> logical_operator;
@@ -89,10 +91,11 @@ RC OptimizeStage::generate_physical_plan(
     unique_ptr<LogicalOperator> &logical_operator, unique_ptr<PhysicalOperator> &physical_operator, Session *session)
 {
   RC rc = RC::SUCCESS;
-  if (session->get_execution_mode() == ExecutionMode::CHUNK_ITERATOR && LogicalOperator::can_generate_vectorized_operator(logical_operator->type())) {
+  if (session->get_execution_mode() == ExecutionMode::CHUNK_ITERATOR &&
+      LogicalOperator::can_generate_vectorized_operator(logical_operator->type())) {
     LOG_TRACE("use chunk iterator");
     session->set_used_chunk_mode(true);
-    rc    = physical_plan_generator_.create_vec(*logical_operator, physical_operator, session);
+    rc = physical_plan_generator_.create_vec(*logical_operator, physical_operator, session);
   } else {
     LOG_TRACE("use tuple iterator");
     session->set_used_chunk_mode(false);
@@ -130,3 +133,4 @@ RC OptimizeStage::create_logical_plan(SQLStageEvent *sql_event, unique_ptr<Logic
 
   return logical_plan_generator_.create(stmt, logical_operator);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/optimize_stage.h b/src/observer/sql/optimizer/optimize_stage.h
index 83c0f9739..7d0885899 100644
--- a/src/observer/sql/optimizer/optimize_stage.h
+++ b/src/observer/sql/optimizer/optimize_stage.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/physical_plan_generator.h"
 #include "sql/optimizer/rewriter.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 class LogicalOperator;
 class Stmt;
@@ -79,3 +81,4 @@ class OptimizeStage
   PhysicalPlanGenerator physical_plan_generator_;  ///< 根据逻辑计划生成物理计划
   Rewriter              rewriter_;                 ///< 逻辑计划改写
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/optimizer_utils.cpp b/src/observer/sql/optimizer/optimizer_utils.cpp
index 37fd1064e..f100cf698 100644
--- a/src/observer/sql/optimizer/optimizer_utils.cpp
+++ b/src/observer/sql/optimizer/optimizer_utils.cpp
@@ -10,55 +10,57 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/optimizer_utils.h"
 
-string OptimizerUtils::dump_physical_plan(const unique_ptr<PhysicalOperator>& children)
+namespace oceanbase {
+
+string OptimizerUtils::dump_physical_plan(const unique_ptr<PhysicalOperator> &children)
 {
-  std::function<void(ostream &, PhysicalOperator *, int, bool, vector<uint8_t> &)> to_string = [&](
-    ostream &os, PhysicalOperator *oper, int level, bool last_child, vector<uint8_t> &ends)
-  {
-    for (int i = 0; i < level - 1; i++) {
-      if (ends[i]) {
-        os << "  ";
-      } else {
-        os << "│ ";
-      }
-    }
-    if (level > 0) {
-      if (last_child) {
-        os << "└─";
-        ends[level - 1] = 1;
-      } else {
-        os << "├─";
-      }
-    }
+  std::function<void(ostream &, PhysicalOperator *, int, bool, vector<uint8_t> &)> to_string =
+      [&](ostream &os, PhysicalOperator *oper, int level, bool last_child, vector<uint8_t> &ends) {
+        for (int i = 0; i < level - 1; i++) {
+          if (ends[i]) {
+            os << "  ";
+          } else {
+            os << "│ ";
+          }
+        }
+        if (level > 0) {
+          if (last_child) {
+            os << "└─";
+            ends[level - 1] = 1;
+          } else {
+            os << "├─";
+          }
+        }
 
-    os << oper->name();
-    string param = oper->param();
-    if (!param.empty()) {
-      os << "(" << param << ")";
-    }
-    os << '\n';
+        os << oper->name();
+        string param = oper->param();
+        if (!param.empty()) {
+          os << "(" << param << ")";
+        }
+        os << '\n';
 
-    if (static_cast<int>(ends.size()) < level + 2) {
-      ends.resize(level + 2);
-    }
-    ends[level + 1] = 0;
+        if (static_cast<int>(ends.size()) < level + 2) {
+          ends.resize(level + 2);
+        }
+        ends[level + 1] = 0;
 
-    vector<unique_ptr<PhysicalOperator>> &children = oper->children();
-    const auto                                 size     = static_cast<int>(children.size());
-    for (auto i = 0; i < size - 1; i++) {
-      to_string(os, children[i].get(), level + 1, false /*last_child*/, ends);
-    }
-    if (size > 0) {
-      to_string(os, children[size - 1].get(), level + 1, true /*last_child*/, ends);
-    }
-  };
+        vector<unique_ptr<PhysicalOperator>> &children = oper->children();
+        const auto                            size     = static_cast<int>(children.size());
+        for (auto i = 0; i < size - 1; i++) {
+          to_string(os, children[i].get(), level + 1, false /*last_child*/, ends);
+        }
+        if (size > 0) {
+          to_string(os, children[size - 1].get(), level + 1, true /*last_child*/, ends);
+        }
+      };
   stringstream ss;
   ss << "OPERATOR(NAME)\n";
 
-  int               level = 0;
+  int             level = 0;
   vector<uint8_t> ends;
   ends.push_back(true);
   to_string(ss, children.get(), level, true /*last_child*/, ends);
 
   return ss.str();
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/optimizer_utils.h b/src/observer/sql/optimizer/optimizer_utils.h
index 6cb2c6529..502253c93 100644
--- a/src/observer/sql/optimizer/optimizer_utils.h
+++ b/src/observer/sql/optimizer/optimizer_utils.h
@@ -14,8 +14,11 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/memory.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class OptimizerUtils
 {
 public:
   static string dump_physical_plan(const unique_ptr<PhysicalOperator> &root);
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/physical_plan_generator.cpp b/src/observer/sql/optimizer/physical_plan_generator.cpp
index 4ce64a24b..994e1b59a 100644
--- a/src/observer/sql/optimizer/physical_plan_generator.cpp
+++ b/src/observer/sql/optimizer/physical_plan_generator.cpp
@@ -46,7 +46,10 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
-RC PhysicalPlanGenerator::create(LogicalOperator &logical_operator, unique_ptr<PhysicalOperator> &oper, Session* session)
+namespace oceanbase {
+
+RC PhysicalPlanGenerator::create(
+    LogicalOperator &logical_operator, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   RC rc = RC::SUCCESS;
 
@@ -95,7 +98,8 @@ RC PhysicalPlanGenerator::create(LogicalOperator &logical_operator, unique_ptr<P
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_vec(LogicalOperator &logical_operator, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_vec(
+    LogicalOperator &logical_operator, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   RC rc = RC::SUCCESS;
 
@@ -120,7 +124,8 @@ RC PhysicalPlanGenerator::create_vec(LogicalOperator &logical_operator, unique_p
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_plan(TableGetLogicalOperator &table_get_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    TableGetLogicalOperator &table_get_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<Expression>> &predicates = table_get_oper.predicates();
   // 看看是否有可以用于索引查找的表达式
@@ -191,7 +196,8 @@ RC PhysicalPlanGenerator::create_plan(TableGetLogicalOperator &table_get_oper, u
   return RC::SUCCESS;
 }
 
-RC PhysicalPlanGenerator::create_plan(PredicateLogicalOperator &pred_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    PredicateLogicalOperator &pred_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<LogicalOperator>> &children_opers = pred_oper.children();
   ASSERT(children_opers.size() == 1, "predicate logical operator's sub oper number should be 1");
@@ -214,7 +220,8 @@ RC PhysicalPlanGenerator::create_plan(PredicateLogicalOperator &pred_oper, uniqu
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_plan(ProjectLogicalOperator &project_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    ProjectLogicalOperator &project_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<LogicalOperator>> &child_opers = project_oper.children();
 
@@ -242,7 +249,8 @@ RC PhysicalPlanGenerator::create_plan(ProjectLogicalOperator &project_oper, uniq
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_plan(InsertLogicalOperator &insert_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    InsertLogicalOperator &insert_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   Table                  *table           = insert_oper.table();
   vector<Value>          &values          = insert_oper.values();
@@ -251,7 +259,8 @@ RC PhysicalPlanGenerator::create_plan(InsertLogicalOperator &insert_oper, unique
   return RC::SUCCESS;
 }
 
-RC PhysicalPlanGenerator::create_plan(DeleteLogicalOperator &delete_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    DeleteLogicalOperator &delete_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<LogicalOperator>> &child_opers = delete_oper.children();
 
@@ -276,7 +285,8 @@ RC PhysicalPlanGenerator::create_plan(DeleteLogicalOperator &delete_oper, unique
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_plan(ExplainLogicalOperator &explain_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    ExplainLogicalOperator &explain_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<LogicalOperator>> &child_opers = explain_oper.children();
 
@@ -298,7 +308,8 @@ RC PhysicalPlanGenerator::create_plan(ExplainLogicalOperator &explain_oper, uniq
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_plan(JoinLogicalOperator &join_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    JoinLogicalOperator &join_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   RC rc = RC::SUCCESS;
 
@@ -333,7 +344,8 @@ bool PhysicalPlanGenerator::can_use_hash_join(JoinLogicalOperator &join_oper)
   return false;
 }
 
-RC PhysicalPlanGenerator::create_plan(CalcLogicalOperator &logical_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    CalcLogicalOperator &logical_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   RC rc = RC::SUCCESS;
 
@@ -342,17 +354,18 @@ RC PhysicalPlanGenerator::create_plan(CalcLogicalOperator &logical_oper, unique_
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_plan(GroupByLogicalOperator &logical_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_plan(
+    GroupByLogicalOperator &logical_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   RC rc = RC::SUCCESS;
 
-  vector<unique_ptr<Expression>> &group_by_expressions = logical_oper.group_by_expressions();
+  vector<unique_ptr<Expression>>     &group_by_expressions = logical_oper.group_by_expressions();
   unique_ptr<GroupByPhysicalOperator> group_by_oper;
   if (group_by_expressions.empty()) {
     group_by_oper = make_unique<ScalarGroupByPhysicalOperator>(std::move(logical_oper.aggregate_expressions()));
   } else {
-    group_by_oper = make_unique<HashGroupByPhysicalOperator>(std::move(logical_oper.group_by_expressions()),
-        std::move(logical_oper.aggregate_expressions()));
+    group_by_oper = make_unique<HashGroupByPhysicalOperator>(
+        std::move(logical_oper.group_by_expressions()), std::move(logical_oper.aggregate_expressions()));
   }
 
   ASSERT(logical_oper.children().size() == 1, "group by operator should have 1 child");
@@ -371,11 +384,13 @@ RC PhysicalPlanGenerator::create_plan(GroupByLogicalOperator &logical_oper, uniq
   return rc;
 }
 
-RC PhysicalPlanGenerator::create_vec_plan(TableGetLogicalOperator &table_get_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_vec_plan(
+    TableGetLogicalOperator &table_get_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<Expression>> &predicates = table_get_oper.predicates();
-  Table *table = table_get_oper.table();
-  TableScanVecPhysicalOperator *table_scan_oper = new TableScanVecPhysicalOperator(table, table_get_oper.read_write_mode());
+  Table                          *table      = table_get_oper.table();
+  TableScanVecPhysicalOperator   *table_scan_oper =
+      new TableScanVecPhysicalOperator(table, table_get_oper.read_write_mode());
   table_scan_oper->set_predicates(std::move(predicates));
   oper = unique_ptr<PhysicalOperator>(table_scan_oper);
   LOG_TRACE("use vectorized table scan");
@@ -383,16 +398,16 @@ RC PhysicalPlanGenerator::create_vec_plan(TableGetLogicalOperator &table_get_ope
   return RC::SUCCESS;
 }
 
-RC PhysicalPlanGenerator::create_vec_plan(GroupByLogicalOperator &logical_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_vec_plan(
+    GroupByLogicalOperator &logical_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
-  RC rc = RC::SUCCESS;
+  RC                           rc            = RC::SUCCESS;
   unique_ptr<PhysicalOperator> physical_oper = nullptr;
   if (logical_oper.group_by_expressions().empty()) {
     physical_oper = make_unique<AggregateVecPhysicalOperator>(std::move(logical_oper.aggregate_expressions()));
   } else {
     physical_oper = make_unique<GroupByVecPhysicalOperator>(
-      std::move(logical_oper.group_by_expressions()), std::move(logical_oper.aggregate_expressions()));
-
+        std::move(logical_oper.group_by_expressions()), std::move(logical_oper.aggregate_expressions()));
   }
 
   ASSERT(logical_oper.children().size() == 1, "group by operator should have 1 child");
@@ -413,7 +428,8 @@ RC PhysicalPlanGenerator::create_vec_plan(GroupByLogicalOperator &logical_oper,
   return RC::SUCCESS;
 }
 
-RC PhysicalPlanGenerator::create_vec_plan(ProjectLogicalOperator &project_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_vec_plan(
+    ProjectLogicalOperator &project_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<LogicalOperator>> &child_opers = project_oper.children();
 
@@ -447,8 +463,8 @@ RC PhysicalPlanGenerator::create_vec_plan(ProjectLogicalOperator &project_oper,
   return rc;
 }
 
-
-RC PhysicalPlanGenerator::create_vec_plan(ExplainLogicalOperator &explain_oper, unique_ptr<PhysicalOperator> &oper, Session* session)
+RC PhysicalPlanGenerator::create_vec_plan(
+    ExplainLogicalOperator &explain_oper, unique_ptr<PhysicalOperator> &oper, Session *session)
 {
   vector<unique_ptr<LogicalOperator>> &child_opers = explain_oper.children();
 
@@ -469,3 +485,4 @@ RC PhysicalPlanGenerator::create_vec_plan(ExplainLogicalOperator &explain_oper,
   oper = std::move(explain_physical_oper);
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/physical_plan_generator.h b/src/observer/sql/optimizer/physical_plan_generator.h
index 85f2e27d2..eae58dad6 100644
--- a/src/observer/sql/optimizer/physical_plan_generator.h
+++ b/src/observer/sql/optimizer/physical_plan_generator.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/logical_operator.h"
 #include "sql/operator/physical_operator.h"
 
+namespace oceanbase {
+
 class Session;
 class TableGetLogicalOperator;
 class PredicateLogicalOperator;
@@ -62,3 +64,4 @@ class PhysicalPlanGenerator
   // TODO: remove this and add CBO rules
   bool can_use_hash_join(JoinLogicalOperator &logical_oper);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/predicate_pushdown_rewriter.cpp b/src/observer/sql/optimizer/predicate_pushdown_rewriter.cpp
index f67cc551d..592fc3791 100644
--- a/src/observer/sql/optimizer/predicate_pushdown_rewriter.cpp
+++ b/src/observer/sql/optimizer/predicate_pushdown_rewriter.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/operator/logical_operator.h"
 #include "sql/operator/table_get_logical_operator.h"
 
+namespace oceanbase {
+
 RC PredicatePushdownRewriter::rewrite(unique_ptr<LogicalOperator> &oper, bool &change_made)
 {
   RC rc = RC::SUCCESS;
@@ -41,7 +43,7 @@ RC PredicatePushdownRewriter::rewrite(unique_ptr<LogicalOperator> &oper, bool &c
     return rc;
   }
 
-  unique_ptr<Expression>             &predicate_expr = predicate_oper_exprs.front();
+  unique_ptr<Expression>        &predicate_expr = predicate_oper_exprs.front();
   vector<unique_ptr<Expression>> pushdown_exprs;
   rc = get_exprs_can_pushdown(predicate_expr, pushdown_exprs);
   if (rc != RC::SUCCESS) {
@@ -124,3 +126,4 @@ RC PredicatePushdownRewriter::get_exprs_can_pushdown(
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/predicate_pushdown_rewriter.h b/src/observer/sql/optimizer/predicate_pushdown_rewriter.h
index 5fbc4510a..ccf8f1e1e 100644
--- a/src/observer/sql/optimizer/predicate_pushdown_rewriter.h
+++ b/src/observer/sql/optimizer/predicate_pushdown_rewriter.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "sql/optimizer/rewrite_rule.h"
 
+namespace oceanbase {
+
 /**
  * @brief 将一些谓词表达式下推到表数据扫描中
  * @ingroup Rewriter
@@ -34,3 +36,4 @@ class PredicatePushdownRewriter : public RewriteRule
   RC   get_exprs_can_pushdown(unique_ptr<Expression> &expr, vector<unique_ptr<Expression>> &pushdown_exprs);
   bool is_empty_predicate(unique_ptr<Expression> &expr);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/predicate_rewrite.cpp b/src/observer/sql/optimizer/predicate_rewrite.cpp
index 7444efd68..a0c0a1e73 100644
--- a/src/observer/sql/optimizer/predicate_rewrite.cpp
+++ b/src/observer/sql/optimizer/predicate_rewrite.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/predicate_rewrite.h"
 #include "sql/operator/logical_operator.h"
 
+namespace oceanbase {
+
 RC PredicateRewriteRule::rewrite(unique_ptr<LogicalOperator> &oper, bool &change_made)
 {
   vector<unique_ptr<LogicalOperator>> &child_opers = oper->children();
@@ -56,3 +58,4 @@ RC PredicateRewriteRule::rewrite(unique_ptr<LogicalOperator> &oper, bool &change
   change_made = true;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/predicate_rewrite.h b/src/observer/sql/optimizer/predicate_rewrite.h
index 193742dfa..1c16ff32f 100644
--- a/src/observer/sql/optimizer/predicate_rewrite.h
+++ b/src/observer/sql/optimizer/predicate_rewrite.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/optimizer/rewrite_rule.h"
 
+namespace oceanbase {
+
 /**
  * @brief 谓词重写规则
  * @ingroup Rewriter
@@ -29,3 +31,4 @@ class PredicateRewriteRule : public RewriteRule
 
   RC rewrite(unique_ptr<LogicalOperator> &oper, bool &change_made) override;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/predicate_to_join_rule.h b/src/observer/sql/optimizer/predicate_to_join_rule.h
index 4a91f3eb9..5ad6ea1dd 100644
--- a/src/observer/sql/optimizer/predicate_to_join_rule.h
+++ b/src/observer/sql/optimizer/predicate_to_join_rule.h
@@ -13,9 +13,12 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "sql/optimizer/rewrite_rule.h"
 
+namespace oceanbase {
+
 /**
  * @brief 将一些谓词表达式下推到join中
  * @ingroup Rewriter
  */
 class PredicateToJoinRewriter
 {};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/rewrite_rule.h b/src/observer/sql/optimizer/rewrite_rule.h
index 894273d4a..bd2efeb00 100644
--- a/src/observer/sql/optimizer/rewrite_rule.h
+++ b/src/observer/sql/optimizer/rewrite_rule.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/lang/memory.h"
 
+namespace oceanbase {
+
 class LogicalOperator;
 class Expression;
 
@@ -44,3 +46,4 @@ class ExpressionRewriteRule
 
   virtual RC rewrite(unique_ptr<Expression> &expr, bool &change_made) = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/rewriter.cpp b/src/observer/sql/optimizer/rewriter.cpp
index fcb189b1b..ac4d8e326 100644
--- a/src/observer/sql/optimizer/rewriter.cpp
+++ b/src/observer/sql/optimizer/rewriter.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/optimizer/predicate_pushdown_rewriter.h"
 #include "sql/optimizer/predicate_rewrite.h"
 
+namespace oceanbase {
+
 Rewriter::Rewriter()
 {
   rewrite_rules_.emplace_back(new ExpressionRewriter);
@@ -64,3 +66,4 @@ RC Rewriter::rewrite(unique_ptr<LogicalOperator> &oper, bool &change_made)
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/optimizer/rewriter.h b/src/observer/sql/optimizer/rewriter.h
index b54fc71f6..e53ed217f 100644
--- a/src/observer/sql/optimizer/rewriter.h
+++ b/src/observer/sql/optimizer/rewriter.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/memory.h"
 #include "common/lang/vector.h"
 
+namespace oceanbase {
+
 class LogicalOperator;
 
 /**
@@ -50,3 +52,4 @@ class Rewriter
 private:
   vector<unique_ptr<RewriteRule>> rewrite_rules_;
 };
+}  // namespace oceanbase
diff --git a/src/observer/sql/optimizer/statistics/table_statistics.h b/src/observer/sql/optimizer/statistics/table_statistics.h
index c1e75e7a6..6fd3698fc 100644
--- a/src/observer/sql/optimizer/statistics/table_statistics.h
+++ b/src/observer/sql/optimizer/statistics/table_statistics.h
@@ -10,5 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #pragma once
 
+namespace oceanbase {
+
 class TableStatistics
-{};
\ No newline at end of file
+{};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/expression_binder.cpp b/src/observer/sql/parser/expression_binder.cpp
index 684ecf468..8ff77c7b1 100644
--- a/src/observer/sql/parser/expression_binder.cpp
+++ b/src/observer/sql/parser/expression_binder.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 Table *BinderContext::find_table(const char *table_name) const
 {
   auto pred = [table_name](Table *table) { return 0 == strcasecmp(table_name, table->name()); };
@@ -384,7 +386,7 @@ RC check_aggregate_expression(AggregateExpr &expression)
   }
 
   // 子表达式中不能再包含聚合表达式
-  function<RC(unique_ptr<Expression>&)> check_aggregate_expr = [&](unique_ptr<Expression> &expr) -> RC {
+  function<RC(unique_ptr<Expression> &)> check_aggregate_expr = [&](unique_ptr<Expression> &expr) -> RC {
     RC rc = RC::SUCCESS;
     if (expr->type() == ExprType::AGGREGATION) {
       LOG_WARN("aggregate expression cannot be nested");
@@ -406,10 +408,10 @@ RC ExpressionBinder::bind_aggregate_expression(
     return RC::SUCCESS;
   }
 
-  auto unbound_aggregate_expr = static_cast<UnboundAggregateExpr *>(expr.get());
-  const char *aggregate_name = unbound_aggregate_expr->aggregate_name();
+  auto                unbound_aggregate_expr = static_cast<UnboundAggregateExpr *>(expr.get());
+  const char         *aggregate_name         = unbound_aggregate_expr->aggregate_name();
   AggregateExpr::Type aggregate_type;
-  RC rc = AggregateExpr::type_from_string(aggregate_name, aggregate_type);
+  RC                  rc = AggregateExpr::type_from_string(aggregate_name, aggregate_type);
   if (OB_FAIL(rc)) {
     LOG_WARN("invalid aggregate name: %s", aggregate_name);
     return rc;
@@ -447,3 +449,4 @@ RC ExpressionBinder::bind_aggregate_expression(
   bound_expressions.emplace_back(std::move(aggregate_expr));
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/expression_binder.h b/src/observer/sql/parser/expression_binder.h
index 9a5e7c9cd..2accb78a2 100644
--- a/src/observer/sql/parser/expression_binder.h
+++ b/src/observer/sql/parser/expression_binder.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/expr/expression.h"
 
+namespace oceanbase {
+
 class BinderContext
 {
 public:
@@ -63,3 +65,4 @@ class ExpressionBinder
 private:
   BinderContext &context_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/parse.cpp b/src/observer/sql/parser/parse.cpp
index 5762452be..3ef65c261 100644
--- a/src/observer/sql/parser/parse.cpp
+++ b/src/observer/sql/parser/parse.cpp
@@ -16,16 +16,15 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "sql/expr/expression.h"
 
+namespace oceanbase {
+
 RC parse(char *st, ParsedSqlNode *sqln);
 
 ParsedSqlNode::ParsedSqlNode() : flag(SCF_ERROR) {}
 
 ParsedSqlNode::ParsedSqlNode(SqlCommandFlag _flag) : flag(_flag) {}
 
-void ParsedSqlResult::add_sql_node(unique_ptr<ParsedSqlNode> sql_node)
-{
-  sql_nodes_.emplace_back(std::move(sql_node));
-}
+void ParsedSqlResult::add_sql_node(unique_ptr<ParsedSqlNode> sql_node) { sql_nodes_.emplace_back(std::move(sql_node)); }
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -36,3 +35,4 @@ RC parse(const char *st, ParsedSqlResult *sql_result)
   sql_parse(st, sql_result);
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/parse.h b/src/observer/sql/parser/parse.h
index 5aaeda3f7..3c99a892d 100644
--- a/src/observer/sql/parser/parse.h
+++ b/src/observer/sql/parser/parse.h
@@ -17,4 +17,7 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "sql/parser/parse_defs.h"
 
+namespace oceanbase {
+
 RC parse(const char *st, ParsedSqlResult *sql_result);
+}
\ No newline at end of file
diff --git a/src/observer/sql/parser/parse_defs.h b/src/observer/sql/parser/parse_defs.h
index 7d9ab7e5a..c07dd07e1 100644
--- a/src/observer/sql/parser/parse_defs.h
+++ b/src/observer/sql/parser/parse_defs.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "common/lang/utility.h"
 
+namespace oceanbase {
+
 class Expression;
 
 /**
@@ -337,3 +339,4 @@ class ParsedSqlResult
 private:
   vector<unique_ptr<ParsedSqlNode>> sql_nodes_;  ///< 这里记录SQL命令。虽然看起来支持多个，但是当前仅处理一个
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/parse_stage.cpp b/src/observer/sql/parser/parse_stage.cpp
index ec92cb46a..f8093cc1e 100644
--- a/src/observer/sql/parser/parse_stage.cpp
+++ b/src/observer/sql/parser/parse_stage.cpp
@@ -26,11 +26,13 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC ParseStage::handle_request(SQLStageEvent *sql_event)
 {
   RC rc = RC::SUCCESS;
 
-  SqlResult         *sql_result = sql_event->session_event()->sql_result();
+  SqlResult    *sql_result = sql_event->session_event()->sql_result();
   const string &sql        = sql_event->sql();
 
   ParsedSqlResult parsed_sql_result;
@@ -59,3 +61,4 @@ RC ParseStage::handle_request(SQLStageEvent *sql_event)
 
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/parse_stage.h b/src/observer/sql/parser/parse_stage.h
index 6d0706949..275a32267 100644
--- a/src/observer/sql/parser/parse_stage.h
+++ b/src/observer/sql/parser/parse_stage.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -27,3 +29,4 @@ class ParseStage
 public:
   RC handle_request(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/resolve_stage.cpp b/src/observer/sql/parser/resolve_stage.cpp
index 810617058..e6e223031 100644
--- a/src/observer/sql/parser/resolve_stage.cpp
+++ b/src/observer/sql/parser/resolve_stage.cpp
@@ -27,6 +27,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC ResolveStage::handle_request(SQLStageEvent *sql_event)
 {
   RC            rc            = RC::SUCCESS;
@@ -56,3 +58,4 @@ RC ResolveStage::handle_request(SQLStageEvent *sql_event)
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/parser/resolve_stage.h b/src/observer/sql/parser/resolve_stage.h
index a049b7951..dff4aa52c 100644
--- a/src/observer/sql/parser/resolve_stage.h
+++ b/src/observer/sql/parser/resolve_stage.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -27,3 +29,4 @@ class ResolveStage
 public:
   RC handle_request(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/plan_cache/plan_cache_stage.h b/src/observer/sql/plan_cache/plan_cache_stage.h
index e4ea51fca..797eceee4 100644
--- a/src/observer/sql/plan_cache/plan_cache_stage.h
+++ b/src/observer/sql/plan_cache/plan_cache_stage.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 /**
  * @brief 尝试从Plan的缓存中获取Plan，如果没有命中，则执行Optimizer
  * @ingroup SQLStage
@@ -24,3 +26,4 @@ See the Mulan PSL v2 for more details. */
  */
 class PlanCacheStage
 {};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/query_cache/query_cache_stage.cpp b/src/observer/sql/query_cache/query_cache_stage.cpp
index ef6ab09f8..f2daf5239 100644
--- a/src/observer/sql/query_cache/query_cache_stage.cpp
+++ b/src/observer/sql/query_cache/query_cache_stage.cpp
@@ -23,7 +23,7 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
-RC QueryCacheStage::handle_request(SQLStageEvent *sql_event)
-{
-  return RC::SUCCESS;
-}
+namespace oceanbase {
+
+RC QueryCacheStage::handle_request(SQLStageEvent *sql_event) { return RC::SUCCESS; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/query_cache/query_cache_stage.h b/src/observer/sql/query_cache/query_cache_stage.h
index 2ffa3979c..7a0eb0229 100644
--- a/src/observer/sql/query_cache/query_cache_stage.h
+++ b/src/observer/sql/query_cache/query_cache_stage.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class SQLStageEvent;
 
 /**
@@ -32,3 +34,4 @@ class QueryCacheStage
 public:
   RC handle_request(SQLStageEvent *sql_event);
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/analyze_table_stmt.cpp b/src/observer/sql/stmt/analyze_table_stmt.cpp
index 9cb029e57..f028c18a2 100644
--- a/src/observer/sql/stmt/analyze_table_stmt.cpp
+++ b/src/observer/sql/stmt/analyze_table_stmt.cpp
@@ -11,6 +11,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/analyze_table_stmt.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
+
 RC AnalyzeTableStmt::create(Db *db, const AnalyzeTableSqlNode &analyze_table, Stmt *&stmt)
 {
   if (db->find_table(analyze_table.relation_name.c_str()) == nullptr) {
@@ -19,3 +21,4 @@ RC AnalyzeTableStmt::create(Db *db, const AnalyzeTableSqlNode &analyze_table, St
   stmt = new AnalyzeTableStmt(analyze_table.relation_name);
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/analyze_table_stmt.h b/src/observer/sql/stmt/analyze_table_stmt.h
index 7730e5c04..7d7952a71 100644
--- a/src/observer/sql/stmt/analyze_table_stmt.h
+++ b/src/observer/sql/stmt/analyze_table_stmt.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Db;
 
 /**
@@ -33,3 +35,4 @@ class AnalyzeTableStmt : public Stmt
 private:
   string table_name_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/calc_stmt.h b/src/observer/sql/stmt/calc_stmt.h
index 4b5fcdf54..ad35a204c 100644
--- a/src/observer/sql/stmt/calc_stmt.h
+++ b/src/observer/sql/stmt/calc_stmt.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/expr/expression.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Db;
 class Table;
 
@@ -48,3 +50,4 @@ class CalcStmt : public Stmt
 private:
   vector<unique_ptr<Expression>> expressions_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/create_index_stmt.cpp b/src/observer/sql/stmt/create_index_stmt.cpp
index 93fae6630..a01ed62b6 100644
--- a/src/observer/sql/stmt/create_index_stmt.cpp
+++ b/src/observer/sql/stmt/create_index_stmt.cpp
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 RC CreateIndexStmt::create(Db *db, const CreateIndexSqlNode &create_index, Stmt *&stmt)
 {
   stmt = nullptr;
@@ -56,3 +58,4 @@ RC CreateIndexStmt::create(Db *db, const CreateIndexSqlNode &create_index, Stmt
   stmt = new CreateIndexStmt(table, field_meta, create_index.index_name);
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/create_index_stmt.h b/src/observer/sql/stmt/create_index_stmt.h
index cbdd8f4d1..57ebb1948 100644
--- a/src/observer/sql/stmt/create_index_stmt.h
+++ b/src/observer/sql/stmt/create_index_stmt.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 struct CreateIndexSqlNode;
 class Table;
 class FieldMeta;
@@ -47,3 +49,4 @@ class CreateIndexStmt : public Stmt
   const FieldMeta *field_meta_ = nullptr;
   string           index_name_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/create_table_stmt.cpp b/src/observer/sql/stmt/create_table_stmt.cpp
index d8a8944c5..29cba6537 100644
--- a/src/observer/sql/stmt/create_table_stmt.cpp
+++ b/src/observer/sql/stmt/create_table_stmt.cpp
@@ -17,18 +17,22 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/create_table_stmt.h"
 #include "event/sql_debug.h"
 
+namespace oceanbase {
+
 RC CreateTableStmt::create(Db *db, const CreateTableSqlNode &create_table, Stmt *&stmt)
 {
   StorageFormat storage_format = get_storage_format(create_table.storage_format.c_str());
   if (storage_format == StorageFormat::UNKNOWN_FORMAT) {
     return RC::INVALID_ARGUMENT;
   }
-  stmt = new CreateTableStmt(create_table.relation_name, create_table.attr_infos, create_table.primary_keys, storage_format);
+  stmt = new CreateTableStmt(
+      create_table.relation_name, create_table.attr_infos, create_table.primary_keys, storage_format);
   sql_debug("create table statement: table name %s", create_table.relation_name.c_str());
   return RC::SUCCESS;
 }
 
-StorageFormat CreateTableStmt::get_storage_format(const char *format_str) {
+StorageFormat CreateTableStmt::get_storage_format(const char *format_str)
+{
   StorageFormat format = StorageFormat::UNKNOWN_FORMAT;
   if (strlen(format_str) == 0) {
     format = StorageFormat::ROW_FORMAT;
@@ -41,3 +45,4 @@ StorageFormat CreateTableStmt::get_storage_format(const char *format_str) {
   }
   return format;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/create_table_stmt.h b/src/observer/sql/stmt/create_table_stmt.h
index 3dd7b17b0..62495f6a9 100644
--- a/src/observer/sql/stmt/create_table_stmt.h
+++ b/src/observer/sql/stmt/create_table_stmt.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Db;
 
 /**
@@ -50,3 +52,4 @@ class CreateTableStmt : public Stmt
   vector<string>          primary_keys_;
   StorageFormat           storage_format_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/delete_stmt.cpp b/src/observer/sql/stmt/delete_stmt.cpp
index 89dce0db8..dec59b169 100644
--- a/src/observer/sql/stmt/delete_stmt.cpp
+++ b/src/observer/sql/stmt/delete_stmt.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/db/db.h"
 #include "storage/table/table.h"
 
+namespace oceanbase {
+
 DeleteStmt::DeleteStmt(Table *table, FilterStmt *filter_stmt) : table_(table), filter_stmt_(filter_stmt) {}
 
 DeleteStmt::~DeleteStmt()
@@ -57,3 +59,4 @@ RC DeleteStmt::create(Db *db, const DeleteSqlNode &delete_sql, Stmt *&stmt)
   stmt = new DeleteStmt(table, filter_stmt);
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/delete_stmt.h b/src/observer/sql/stmt/delete_stmt.h
index 33cda12a6..b4232e3a7 100644
--- a/src/observer/sql/stmt/delete_stmt.h
+++ b/src/observer/sql/stmt/delete_stmt.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/parser/parse_defs.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Table;
 class FilterStmt;
 
@@ -42,3 +44,4 @@ class DeleteStmt : public Stmt
   Table      *table_       = nullptr;
   FilterStmt *filter_stmt_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/desc_table_stmt.cpp b/src/observer/sql/stmt/desc_table_stmt.cpp
index 1f1e65a13..6bcdef616 100644
--- a/src/observer/sql/stmt/desc_table_stmt.cpp
+++ b/src/observer/sql/stmt/desc_table_stmt.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/desc_table_stmt.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
+
 RC DescTableStmt::create(Db *db, const DescTableSqlNode &desc_table, Stmt *&stmt)
 {
   if (db->find_table(desc_table.relation_name.c_str()) == nullptr) {
@@ -23,3 +25,4 @@ RC DescTableStmt::create(Db *db, const DescTableSqlNode &desc_table, Stmt *&stmt
   stmt = new DescTableStmt(desc_table.relation_name);
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
diff --git a/src/observer/sql/stmt/desc_table_stmt.h b/src/observer/sql/stmt/desc_table_stmt.h
index 9e57a8a67..bfccd6236 100644
--- a/src/observer/sql/stmt/desc_table_stmt.h
+++ b/src/observer/sql/stmt/desc_table_stmt.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Db;
 
 /**
@@ -38,3 +40,4 @@ class DescTableStmt : public Stmt
 private:
   string table_name_;
 };
+}  // namespace oceanbase
diff --git a/src/observer/sql/stmt/exit_stmt.h b/src/observer/sql/stmt/exit_stmt.h
index 228223bd6..4efa2460a 100644
--- a/src/observer/sql/stmt/exit_stmt.h
+++ b/src/observer/sql/stmt/exit_stmt.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief Exit 语句，表示断开连接，现在什么成员都没有
  * @ingroup Statement
@@ -33,4 +35,5 @@ class ExitStmt : public Stmt
     stmt = new ExitStmt();
     return RC::SUCCESS;
   }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/explain_stmt.cpp b/src/observer/sql/stmt/explain_stmt.cpp
index 7efea6a2b..6a085b9e1 100644
--- a/src/observer/sql/stmt/explain_stmt.cpp
+++ b/src/observer/sql/stmt/explain_stmt.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 ExplainStmt::ExplainStmt(unique_ptr<Stmt> child_stmt) : child_stmt_(std::move(child_stmt)) {}
 
 RC ExplainStmt::create(Db *db, const ExplainSqlNode &explain, Stmt *&stmt)
@@ -28,6 +30,7 @@ RC ExplainStmt::create(Db *db, const ExplainSqlNode &explain, Stmt *&stmt)
   }
 
   unique_ptr<Stmt> child_stmt_ptr = unique_ptr<Stmt>(child_stmt);
-  stmt                                 = new ExplainStmt(std::move(child_stmt_ptr));
+  stmt                            = new ExplainStmt(std::move(child_stmt_ptr));
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/explain_stmt.h b/src/observer/sql/stmt/explain_stmt.h
index 3634f07cd..23763fdd3 100644
--- a/src/observer/sql/stmt/explain_stmt.h
+++ b/src/observer/sql/stmt/explain_stmt.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief explain语句
  * @ingroup Statement
@@ -35,3 +37,4 @@ class ExplainStmt : public Stmt
 private:
   unique_ptr<Stmt> child_stmt_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/filter_stmt.cpp b/src/observer/sql/stmt/filter_stmt.cpp
index aa078bcbb..9a27f8c64 100644
--- a/src/observer/sql/stmt/filter_stmt.cpp
+++ b/src/observer/sql/stmt/filter_stmt.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/db/db.h"
 #include "storage/table/table.h"
 
+namespace oceanbase {
+
 FilterStmt::~FilterStmt()
 {
   for (FilterUnit *unit : filter_units_) {
@@ -50,8 +52,8 @@ RC FilterStmt::create(Db *db, Table *default_table, unordered_map<string, Table
   return rc;
 }
 
-RC get_table_and_field(Db *db, Table *default_table, unordered_map<string, Table *> *tables,
-    const RelAttrSqlNode &attr, Table *&table, const FieldMeta *&field)
+RC get_table_and_field(Db *db, Table *default_table, unordered_map<string, Table *> *tables, const RelAttrSqlNode &attr,
+    Table *&table, const FieldMeta *&field)
 {
   if (common::is_blank(attr.relation_name.c_str())) {
     table = default_table;
@@ -130,3 +132,4 @@ RC FilterStmt::create_filter_unit(Db *db, Table *default_table, unordered_map<st
   // 检查两个类型是否能够比较
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/filter_stmt.h b/src/observer/sql/stmt/filter_stmt.h
index 35b3be1ec..0cdbf46aa 100644
--- a/src/observer/sql/stmt/filter_stmt.h
+++ b/src/observer/sql/stmt/filter_stmt.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/parser/parse_defs.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Db;
 class Table;
 class FieldMeta;
@@ -88,3 +90,4 @@ class FilterStmt
 private:
   vector<FilterUnit *> filter_units_;  // 默认当前都是AND关系
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/help_stmt.h b/src/observer/sql/stmt/help_stmt.h
index 1946b56cb..b63bc2c4b 100644
--- a/src/observer/sql/stmt/help_stmt.h
+++ b/src/observer/sql/stmt/help_stmt.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief Help 语句，现在什么成员都没有
  * @ingroup Statement
@@ -36,4 +38,5 @@ class HelpStmt : public Stmt
     stmt = new HelpStmt();
     return RC::SUCCESS;
   }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/insert_stmt.cpp b/src/observer/sql/stmt/insert_stmt.cpp
index 96ced424f..61c53c987 100644
--- a/src/observer/sql/stmt/insert_stmt.cpp
+++ b/src/observer/sql/stmt/insert_stmt.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/db/db.h"
 #include "storage/table/table.h"
 
+namespace oceanbase {
+
 InsertStmt::InsertStmt(Table *table, const Value *values, int value_amount)
     : table_(table), values_(values), value_amount_(value_amount)
 {}
@@ -51,3 +53,4 @@ RC InsertStmt::create(Db *db, const InsertSqlNode &inserts, Stmt *&stmt)
   stmt = new InsertStmt(table, values, value_num);
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/insert_stmt.h b/src/observer/sql/stmt/insert_stmt.h
index 51c162ac8..19d823f1b 100644
--- a/src/observer/sql/stmt/insert_stmt.h
+++ b/src/observer/sql/stmt/insert_stmt.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Table;
 class Db;
 
@@ -45,3 +47,4 @@ class InsertStmt : public Stmt
   const Value *values_       = nullptr;
   int          value_amount_ = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/load_data_stmt.cpp b/src/observer/sql/stmt/load_data_stmt.cpp
index 37335dfa7..e5a07dbfe 100644
--- a/src/observer/sql/stmt/load_data_stmt.cpp
+++ b/src/observer/sql/stmt/load_data_stmt.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC LoadDataStmt::create(Db *db, const LoadDataSqlNode &load_data, Stmt *&stmt)
 {
   RC rc = RC::SUCCESS;
@@ -55,3 +57,4 @@ RC LoadDataStmt::create(Db *db, const LoadDataSqlNode &load_data, Stmt *&stmt)
   stmt = new LoadDataStmt(table, load_data.file_name.c_str(), load_data.terminated[1], load_data.enclosed[1]);
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/load_data_stmt.h b/src/observer/sql/stmt/load_data_stmt.h
index 5e5c49b67..8472792f5 100644
--- a/src/observer/sql/stmt/load_data_stmt.h
+++ b/src/observer/sql/stmt/load_data_stmt.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Table;
 
 class LoadDataStmt : public Stmt
@@ -41,3 +43,4 @@ class LoadDataStmt : public Stmt
   char   terminated_;
   char   enclosed_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/select_stmt.cpp b/src/observer/sql/stmt/select_stmt.cpp
index a51d9e794..1d68247e6 100644
--- a/src/observer/sql/stmt/select_stmt.cpp
+++ b/src/observer/sql/stmt/select_stmt.cpp
@@ -23,6 +23,8 @@ See the Mulan PSL v2 for more details. */
 using namespace std;
 using namespace common;
 
+namespace oceanbase {
+
 SelectStmt::~SelectStmt()
 {
   if (nullptr != filter_stmt_) {
@@ -63,8 +65,8 @@ RC SelectStmt::create(Db *db, SelectSqlNode &select_sql, Stmt *&stmt)
 
   // collect query fields in `select` statement
   vector<unique_ptr<Expression>> bound_expressions;
-  ExpressionBinder expression_binder(binder_context);
-  
+  ExpressionBinder               expression_binder(binder_context);
+
   for (unique_ptr<Expression> &expression : select_sql.expressions) {
     RC rc = expression_binder.bind_expression(expression, bound_expressions);
     if (OB_FAIL(rc)) {
@@ -107,6 +109,7 @@ RC SelectStmt::create(Db *db, SelectSqlNode &select_sql, Stmt *&stmt)
   select_stmt->query_expressions_.swap(bound_expressions);
   select_stmt->filter_stmt_ = filter_stmt;
   select_stmt->group_by_.swap(group_by_expressions);
-  stmt                      = select_stmt;
+  stmt = select_stmt;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/select_stmt.h b/src/observer/sql/stmt/select_stmt.h
index 5a736d9d0..ba0544120 100644
--- a/src/observer/sql/stmt/select_stmt.h
+++ b/src/observer/sql/stmt/select_stmt.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/stmt.h"
 #include "storage/field/field.h"
 
+namespace oceanbase {
+
 class FieldMeta;
 class FilterStmt;
 class Db;
@@ -51,3 +53,4 @@ class SelectStmt : public Stmt
   FilterStmt                    *filter_stmt_ = nullptr;
   vector<unique_ptr<Expression>> group_by_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/set_variable_stmt.h b/src/observer/sql/stmt/set_variable_stmt.h
index 93eb82aaa..51701610c 100644
--- a/src/observer/sql/stmt/set_variable_stmt.h
+++ b/src/observer/sql/stmt/set_variable_stmt.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief SetVairable 语句，设置变量，当前是会话变量，但是只有会话变量，没有全局变量
  * @ingroup Statement
@@ -43,4 +45,5 @@ class SetVariableStmt : public Stmt
 
 private:
   SetVariableSqlNode set_variable_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/show_tables_stmt.h b/src/observer/sql/stmt/show_tables_stmt.h
index 601a1d568..ec00f6a25 100644
--- a/src/observer/sql/stmt/show_tables_stmt.h
+++ b/src/observer/sql/stmt/show_tables_stmt.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Db;
 
 /**
@@ -39,4 +41,5 @@ class ShowTablesStmt : public Stmt
     stmt = new ShowTablesStmt();
     return RC::SUCCESS;
   }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/stmt.cpp b/src/observer/sql/stmt/stmt.cpp
index 2664aaf60..d2cde730c 100644
--- a/src/observer/sql/stmt/stmt.cpp
+++ b/src/observer/sql/stmt/stmt.cpp
@@ -31,6 +31,8 @@ See the Mulan PSL v2 for more details. */
 #include "sql/stmt/trx_begin_stmt.h"
 #include "sql/stmt/trx_end_stmt.h"
 
+namespace oceanbase {
+
 bool stmt_type_ddl(StmtType type)
 {
   switch (type) {
@@ -76,7 +78,7 @@ RC Stmt::create_stmt(Db *db, ParsedSqlNode &sql_node, Stmt *&stmt)
       return DescTableStmt::create(db, sql_node.desc_table, stmt);
     }
 
-    case SCF_ANALYZE_TABLE: { 
+    case SCF_ANALYZE_TABLE: {
       return AnalyzeTableStmt::create(db, sql_node.analyze_table, stmt);
     }
 
@@ -119,3 +121,4 @@ RC Stmt::create_stmt(Db *db, ParsedSqlNode &sql_node, Stmt *&stmt)
   }
   return RC::UNIMPLEMENTED;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/stmt.h b/src/observer/sql/stmt/stmt.h
index 4c9b4b03e..e40730957 100644
--- a/src/observer/sql/stmt/stmt.h
+++ b/src/observer/sql/stmt/stmt.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "sql/parser/parse_defs.h"
 
+namespace oceanbase {
+
 class Db;
 
 /**
@@ -92,3 +94,4 @@ class Stmt
 
 private:
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/trx_begin_stmt.h b/src/observer/sql/stmt/trx_begin_stmt.h
index afdfaf104..74c1f2d4b 100644
--- a/src/observer/sql/stmt/trx_begin_stmt.h
+++ b/src/observer/sql/stmt/trx_begin_stmt.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief 事务的Begin 语句，现在什么成员都没有
  * @ingroup Statement
@@ -36,4 +38,5 @@ class TrxBeginStmt : public Stmt
     stmt = new TrxBeginStmt();
     return RC::SUCCESS;
   }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/trx_end_stmt.h b/src/observer/sql/stmt/trx_end_stmt.h
index 30454ecf6..6214b4f51 100644
--- a/src/observer/sql/stmt/trx_end_stmt.h
+++ b/src/observer/sql/stmt/trx_end_stmt.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 /**
  * @brief 事务的 Commit/Rollback 语句，现在什么成员都没有
  * @ingroup Statement
@@ -40,4 +42,5 @@ class TrxEndStmt : public Stmt
 
 private:
   StmtType type_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/update_stmt.cpp b/src/observer/sql/stmt/update_stmt.cpp
index 92df6a6dc..46810ae91 100644
--- a/src/observer/sql/stmt/update_stmt.cpp
+++ b/src/observer/sql/stmt/update_stmt.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/stmt/update_stmt.h"
 
+namespace oceanbase {
+
 UpdateStmt::UpdateStmt(Table *table, Value *values, int value_amount)
     : table_(table), values_(values), value_amount_(value_amount)
 {}
@@ -24,3 +26,4 @@ RC UpdateStmt::create(Db *db, const UpdateSqlNode &update, Stmt *&stmt)
   stmt = nullptr;
   return RC::INTERNAL;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/sql/stmt/update_stmt.h b/src/observer/sql/stmt/update_stmt.h
index 28e13268e..50b679545 100644
--- a/src/observer/sql/stmt/update_stmt.h
+++ b/src/observer/sql/stmt/update_stmt.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "sql/stmt/stmt.h"
 
+namespace oceanbase {
+
 class Table;
 
 /**
@@ -42,3 +44,4 @@ class UpdateStmt : public Stmt
   Value *values_       = nullptr;
   int    value_amount_ = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/buffer_pool_log.cpp b/src/observer/storage/buffer/buffer_pool_log.cpp
index b0fb2c961..70f42e7ce 100644
--- a/src/observer/storage/buffer/buffer_pool_log.cpp
+++ b/src/observer/storage/buffer/buffer_pool_log.cpp
@@ -17,10 +17,11 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/log_handler.h"
 #include "storage/clog/log_entry.h"
 
+namespace oceanbase {
+
 string BufferPoolLogEntry::to_string() const
 {
-  return string("buffer_pool_id=") + std::to_string(buffer_pool_id) +
-         ", page_num=" + std::to_string(page_num) +
+  return string("buffer_pool_id=") + std::to_string(buffer_pool_id) + ", page_num=" + std::to_string(page_num) +
          ", operation_type=" + BufferPoolOperation(operation_type).to_string();
 }
 
@@ -40,25 +41,22 @@ RC BufferPoolLogHandler::deallocate_page(PageNum page_num, LSN &lsn)
   return append_log(BufferPoolOperation::Type::DEALLOCATE, page_num, lsn);
 }
 
-RC BufferPoolLogHandler::flush_page(Page &page)
-{
-  return log_handler_.wait_lsn(page.lsn);
-}
+RC BufferPoolLogHandler::flush_page(Page &page) { return log_handler_.wait_lsn(page.lsn); }
 
 RC BufferPoolLogHandler::append_log(BufferPoolOperation::Type type, PageNum page_num, LSN &lsn)
 {
   BufferPoolLogEntry log;
   log.buffer_pool_id = buffer_pool_.id();
-  log.page_num = page_num;
+  log.page_num       = page_num;
   log.operation_type = BufferPoolOperation(type).type_id();
 
-  return log_handler_.append(lsn, LogModule::Id::BUFFER_POOL, span<const char>(reinterpret_cast<const char *>(&log), sizeof(log)));
+  return log_handler_.append(
+      lsn, LogModule::Id::BUFFER_POOL, span<const char>(reinterpret_cast<const char *>(&log), sizeof(log)));
 }
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 // BufferPoolLogReplayer
-BufferPoolLogReplayer::BufferPoolLogReplayer(BufferPoolManager &bp_manager) : bp_manager_(bp_manager)
-{}
+BufferPoolLogReplayer::BufferPoolLogReplayer(BufferPoolManager &bp_manager) : bp_manager_(bp_manager) {}
 
 RC BufferPoolLogReplayer::replay(const LogEntry &entry)
 {
@@ -71,10 +69,10 @@ RC BufferPoolLogReplayer::replay(const LogEntry &entry)
   auto log = reinterpret_cast<const BufferPoolLogEntry *>(entry.data());
 
   LOG_TRACE("replay buffer pool log. entry=%s, log=%s", entry.to_string().c_str(), log->to_string().c_str());
-  
-  int32_t buffer_pool_id = log->buffer_pool_id;
-  DiskBufferPool *buffer_pool = nullptr;
-  RC rc = bp_manager_.get_buffer_pool(buffer_pool_id, buffer_pool);
+
+  int32_t         buffer_pool_id = log->buffer_pool_id;
+  DiskBufferPool *buffer_pool    = nullptr;
+  RC              rc             = bp_manager_.get_buffer_pool(buffer_pool_id, buffer_pool);
   if (OB_FAIL(rc) || buffer_pool == nullptr) {
     LOG_ERROR("failed to get buffer pool. rc=%s, buffer pool=%p, log=%s, %s", 
               strrc(rc), buffer_pool, entry.to_string().c_str(), log->to_string().c_str());
@@ -82,15 +80,13 @@ RC BufferPoolLogReplayer::replay(const LogEntry &entry)
   }
 
   BufferPoolOperation operation(log->operation_type);
-  switch (operation.type())
-  {
-    case BufferPoolOperation::Type::ALLOCATE:
-      return buffer_pool->redo_allocate_page(entry.lsn(), log->page_num);
-    case BufferPoolOperation::Type::DEALLOCATE:
-      return buffer_pool->redo_deallocate_page(entry.lsn(), log->page_num);
+  switch (operation.type()) {
+    case BufferPoolOperation::Type::ALLOCATE: return buffer_pool->redo_allocate_page(entry.lsn(), log->page_num);
+    case BufferPoolOperation::Type::DEALLOCATE: return buffer_pool->redo_deallocate_page(entry.lsn(), log->page_num);
     default:
       LOG_ERROR("unknown buffer pool operation. operation=%s", operation.to_string().c_str());
       return RC::INTERNAL;
   }
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/buffer_pool_log.h b/src/observer/storage/buffer/buffer_pool_log.h
index 604c01971..af87b7033 100644
--- a/src/observer/storage/buffer/buffer_pool_log.h
+++ b/src/observer/storage/buffer/buffer_pool_log.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "storage/clog/log_replayer.h"
 
+namespace oceanbase {
+
 class DiskBufferPool;
 class BufferPoolManager;
 class LogHandler;
@@ -127,3 +129,4 @@ class BufferPoolLogReplayer final : public LogReplayer
 private:
   BufferPoolManager &bp_manager_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/disk_buffer_pool.cpp b/src/observer/storage/buffer/disk_buffer_pool.cpp
index df656d76c..183d5befc 100644
--- a/src/observer/storage/buffer/disk_buffer_pool.cpp
+++ b/src/observer/storage/buffer/disk_buffer_pool.cpp
@@ -25,6 +25,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 static const int MEM_POOL_ITEM_NUM = 20;
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -103,7 +105,7 @@ int BPFrameManager::purge_frames(int count, function<RC(Frame *frame)> purger)
 
 Frame *BPFrameManager::get(int buffer_pool_id, PageNum page_num)
 {
-  FrameId                     frame_id(buffer_pool_id, page_num);
+  FrameId frame_id(buffer_pool_id, page_num);
 
   lock_guard<mutex> lock_guard(lock_);
   return get_internal(frame_id);
@@ -126,7 +128,7 @@ Frame *BPFrameManager::alloc(int buffer_pool_id, PageNum page_num)
 
   lock_guard<mutex> lock_guard(lock_);
 
-  Frame                      *frame = get_internal(frame_id);
+  Frame *frame = get_internal(frame_id);
   if (frame != nullptr) {
     return frame;
   }
@@ -172,7 +174,7 @@ list<Frame *> BPFrameManager::find_list(int buffer_pool_id)
   lock_guard<mutex> lock_guard(lock_);
 
   list<Frame *> frames;
-  auto               fetcher = [&frames, buffer_pool_id](const FrameId &frame_id, Frame *const frame) -> bool {
+  auto          fetcher = [&frames, buffer_pool_id](const FrameId &frame_id, Frame *const frame) -> bool {
     if (buffer_pool_id == frame_id.buffer_pool_id()) {
       frame->pin();
       frames.push_back(frame);
@@ -215,9 +217,12 @@ RC BufferPoolIterator::reset()
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-DiskBufferPool::DiskBufferPool(
-    BufferPoolManager &bp_manager, BPFrameManager &frame_manager, DoubleWriteBuffer &dblwr_manager, LogHandler &log_handler)
-    : bp_manager_(bp_manager), frame_manager_(frame_manager), dblwr_manager_(dblwr_manager), log_handler_(*this, log_handler)
+DiskBufferPool::DiskBufferPool(BufferPoolManager &bp_manager, BPFrameManager &frame_manager,
+    DoubleWriteBuffer &dblwr_manager, LogHandler &log_handler)
+    : bp_manager_(bp_manager),
+      frame_manager_(frame_manager),
+      dblwr_manager_(dblwr_manager),
+      log_handler_(*this, log_handler)
 {}
 
 DiskBufferPool::~DiskBufferPool()
@@ -239,7 +244,7 @@ RC DiskBufferPool::open_file(const char *file_name)
   file_desc_ = fd;
 
   Page header_page;
-  int ret = readn(file_desc_, &header_page, sizeof(header_page));
+  int  ret = readn(file_desc_, &header_page, sizeof(header_page));
   if (ret != 0) {
     LOG_ERROR("Failed to read first page of %s, due to %s.", file_name, strerror(errno));
     close(fd);
@@ -248,7 +253,7 @@ RC DiskBufferPool::open_file(const char *file_name)
   }
 
   BPFileHeader *tmp_file_header = reinterpret_cast<BPFileHeader *>(header_page.data);
-  buffer_pool_id_ = tmp_file_header->buffer_pool_id;
+  buffer_pool_id_               = tmp_file_header->buffer_pool_id;
 
   RC rc = allocate_frame(BP_HEADER_PAGE, &hdr_frame_);
   if (rc != RC::SUCCESS) {
@@ -366,7 +371,7 @@ RC DiskBufferPool::allocate_page(Frame **frame)
         // TODO,  do we need clean the loaded page's data?
         hdr_frame_->mark_dirty();
         LSN lsn = 0;
-        rc = log_handler_.allocate_page(i, lsn);
+        rc      = log_handler_.allocate_page(i, lsn);
         if (OB_FAIL(rc)) {
           LOG_ERROR("Failed to log allocate page %d, rc=%s", i, strrc(rc));
           // 忽略了错误
@@ -390,7 +395,7 @@ RC DiskBufferPool::allocate_page(Frame **frame)
   }
 
   LSN lsn = 0;
-  rc = log_handler_.allocate_page(file_header_->page_count, lsn);
+  rc      = log_handler_.allocate_page(file_header_->page_count, lsn);
   if (OB_FAIL(rc)) {
     LOG_ERROR("Failed to log allocate page %d, rc=%s", file_header_->page_count, strrc(rc));
     // 忽略了错误
@@ -440,9 +445,9 @@ RC DiskBufferPool::dispose_page(PageNum page_num)
     LOG_ERROR("Failed to dispose page %d, because it is the first page. filename=%s", page_num, file_name_.c_str());
     return RC::INTERNAL;
   }
-  
+
   scoped_lock lock_guard(lock_);
-  Frame           *used_frame = frame_manager_.get(id(), page_num);
+  Frame      *used_frame = frame_manager_.get(id(), page_num);
   if (used_frame != nullptr) {
     ASSERT("the page try to dispose is in use. frame:%s", used_frame->to_string().c_str());
     frame_manager_.free(id(), page_num, used_frame);
@@ -451,7 +456,7 @@ RC DiskBufferPool::dispose_page(PageNum page_num)
   }
 
   LSN lsn = 0;
-  RC rc = log_handler_.deallocate_page(page_num, lsn);
+  RC  rc  = log_handler_.deallocate_page(page_num, lsn);
   if (OB_FAIL(rc)) {
     LOG_ERROR("Failed to log deallocate page %d, rc=%s", page_num, strrc(rc));
     // ignore error handle
@@ -496,7 +501,7 @@ RC DiskBufferPool::purge_page(PageNum page_num)
 {
   scoped_lock lock_guard(lock_);
 
-  Frame           *used_frame = frame_manager_.get(id(), page_num);
+  Frame *used_frame = frame_manager_.get(id(), page_num);
   if (used_frame != nullptr) {
     return purge_frame(page_num, used_frame);
   }
@@ -651,7 +656,7 @@ RC DiskBufferPool::redo_allocate_page(LSN lsn, PageNum page_num)
   file_header_->page_count++;
   hdr_frame_->set_lsn(lsn);
   hdr_frame_->mark_dirty();
-  
+
   // TODO 应该检查文件是否足够大，包含了当前新分配的页面
 
   Bitmap bitmap(file_header_->bitmap, file_header_->page_count);
@@ -735,13 +740,13 @@ RC DiskBufferPool::check_page_num(PageNum page_num)
 RC DiskBufferPool::load_page(PageNum page_num, Frame *frame)
 {
   Page &page = frame->page();
-  RC rc = dblwr_manager_.read_page(this, page_num, page);
+  RC    rc   = dblwr_manager_.read_page(this, page_num, page);
   if (OB_SUCC(rc)) {
     return rc;
   }
 
   scoped_lock lock_guard(wr_lock_);
-  int64_t          offset = ((int64_t)page_num) * BP_PAGE_SIZE;
+  int64_t     offset = ((int64_t)page_num) * BP_PAGE_SIZE;
   if (lseek(file_desc_, offset, SEEK_SET) == -1) {
     LOG_ERROR("Failed to load page %s:%d, due to failed to lseek:%s.", file_name_.c_str(), page_num, strerror(errno));
 
@@ -895,7 +900,7 @@ RC BufferPoolManager::flush_page(Frame &frame)
   int buffer_pool_id = frame.buffer_pool_id();
 
   scoped_lock lock_guard(lock_);
-  auto             iter = id_to_buffer_pools_.find(buffer_pool_id);
+  auto        iter = id_to_buffer_pools_.find(buffer_pool_id);
   if (iter == id_to_buffer_pools_.end()) {
     LOG_WARN("unknown buffer pool of id %d", buffer_pool_id);
     return RC::INTERNAL;
@@ -916,8 +921,9 @@ RC BufferPoolManager::get_buffer_pool(int32_t id, DiskBufferPool *&bp)
     LOG_WARN("unknown buffer pool of id %d", id);
     return RC::INTERNAL;
   }
-  
+
   bp = iter->second;
   return RC::SUCCESS;
 }
 
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/disk_buffer_pool.h b/src/observer/storage/buffer/disk_buffer_pool.h
index d41d1bd0c..b3c4e4706 100644
--- a/src/observer/storage/buffer/disk_buffer_pool.h
+++ b/src/observer/storage/buffer/disk_buffer_pool.h
@@ -37,6 +37,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/buffer/page.h"
 #include "storage/buffer/buffer_pool_log.h"
 
+namespace oceanbase {
+
 class BufferPoolManager;
 class DiskBufferPool;
 class DoubleWriteBuffer;
@@ -352,5 +354,6 @@ class BufferPoolManager final
   common::Mutex                            lock_;
   unordered_map<string, DiskBufferPool *>  buffer_pools_;
   unordered_map<int32_t, DiskBufferPool *> id_to_buffer_pools_;
-  atomic<int32_t>                          next_buffer_pool_id_{1};  // 系统启动时，会打开所有的表，这样就可以知道当前系统最大的ID是多少了
+  atomic<int32_t> next_buffer_pool_id_{1};  // 系统启动时，会打开所有的表，这样就可以知道当前系统最大的ID是多少了
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/double_write_buffer.cpp b/src/observer/storage/buffer/double_write_buffer.cpp
index 9cfae43cb..714cc79b2 100644
--- a/src/observer/storage/buffer/double_write_buffer.cpp
+++ b/src/observer/storage/buffer/double_write_buffer.cpp
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 struct DoubleWritePage
 {
 public:
@@ -30,25 +32,24 @@ struct DoubleWritePage
 
 public:
   DoubleWritePageKey key;
-  int32_t            page_index = -1; /// 页面在double write buffer文件中的页索引
-  bool               valid = true; /// 表示页面是否有效，在页面被删除时，需要同时标记磁盘上的值。
+  int32_t            page_index = -1;    /// 页面在double write buffer文件中的页索引
+  bool               valid      = true;  /// 表示页面是否有效，在页面被删除时，需要同时标记磁盘上的值。
   Page               page;
 
   static const int32_t SIZE;
 };
 
 DoubleWritePage::DoubleWritePage(int32_t buffer_pool_id, PageNum page_num, int32_t page_index, Page &_page)
-  : key{buffer_pool_id, page_num}, page_index(page_index), page(_page)
+    : key{buffer_pool_id, page_num}, page_index(page_index), page(_page)
 {}
 
 const int32_t DoubleWritePage::SIZE = sizeof(DoubleWritePage);
 
 const int32_t DoubleWriteBufferHeader::SIZE = sizeof(DoubleWriteBufferHeader);
 
-DiskDoubleWriteBuffer::DiskDoubleWriteBuffer(BufferPoolManager &bp_manager, int max_pages /*=16*/) 
-  : max_pages_(max_pages), bp_manager_(bp_manager)
-{
-}
+DiskDoubleWriteBuffer::DiskDoubleWriteBuffer(BufferPoolManager &bp_manager, int max_pages /*=16*/)
+    : max_pages_(max_pages), bp_manager_(bp_manager)
+{}
 
 DiskDoubleWriteBuffer::~DiskDoubleWriteBuffer()
 {
@@ -62,7 +63,7 @@ RC DiskDoubleWriteBuffer::open_file(const char *filename)
     LOG_ERROR("Double write buffer has already opened. file desc=%d", file_desc_);
     return RC::BUFFERPOOL_OPEN;
   }
-  
+
   int fd = open(filename, O_CREAT | O_RDWR, 0644);
   if (fd < 0) {
     LOG_ERROR("Failed to open or creat %s, due to %s.", filename, strerror(errno));
@@ -95,9 +96,9 @@ RC DiskDoubleWriteBuffer::flush_page()
 
 RC DiskDoubleWriteBuffer::add_page(DiskBufferPool *bp, PageNum page_num, Page &page)
 {
-  scoped_lock lock_guard(lock_);
+  scoped_lock        lock_guard(lock_);
   DoubleWritePageKey key{bp->id(), page_num};
-  auto iter = dblwr_pages_.find(key);
+  auto               iter = dblwr_pages_.find(key);
   if (iter != dblwr_pages_.end()) {
     iter->second->page = page;
     LOG_TRACE("[cache hit]add page into double write buffer. buffer_pool_id:%d,page_num:%d,lsn=%d, dwb size=%d",
@@ -145,7 +146,7 @@ RC DiskDoubleWriteBuffer::add_page(DiskBufferPool *bp, PageNum page_num, Page &p
 RC DiskDoubleWriteBuffer::write_page_internal(DoubleWritePage *page)
 {
   int32_t page_index = page->page_index;
-  int64_t offset = page_index * DoubleWritePage::SIZE + DoubleWriteBufferHeader::SIZE;
+  int64_t offset     = page_index * DoubleWritePage::SIZE + DoubleWriteBufferHeader::SIZE;
   if (lseek(file_desc_, offset, SEEK_SET) == -1) {
     LOG_ERROR("Failed to add page %lld of %d due to failed to seek %s.", offset, file_desc_, strerror(errno));
     return RC::IOERR_SEEK;
@@ -179,9 +180,9 @@ RC DiskDoubleWriteBuffer::write_page(DoubleWritePage *dblwr_page)
 
 RC DiskDoubleWriteBuffer::read_page(DiskBufferPool *bp, PageNum page_num, Page &page)
 {
-  scoped_lock lock_guard(lock_);
+  scoped_lock        lock_guard(lock_);
   DoubleWritePageKey key{bp->id(), page_num};
-  auto iter = dblwr_pages_.find(key);
+  auto               iter = dblwr_pages_.find(key);
   if (iter != dblwr_pages_.end()) {
     page = iter->second->page;
     LOG_TRACE("double write buffer read page success. bp id=%d, page_num:%d, lsn:%d", bp->id(), page_num, page.lsn);
@@ -194,7 +195,7 @@ RC DiskDoubleWriteBuffer::read_page(DiskBufferPool *bp, PageNum page_num, Page &
 RC DiskDoubleWriteBuffer::clear_pages(DiskBufferPool *buffer_pool)
 {
   vector<DoubleWritePage *> spec_pages;
-  
+
   auto remove_pred = [&spec_pages, buffer_pool](const pair<DoubleWritePageKey, DoubleWritePage *> &pair) {
     DoubleWritePage *dbl_page = pair.second;
     if (buffer_pool->id() == dbl_page->key.buffer_pool_id) {
@@ -265,9 +266,9 @@ RC DiskDoubleWriteBuffer::load_pages()
       return RC::IOERR_SEEK;
     }
 
-    auto dblwr_page = make_unique<DoubleWritePage>();
-    Page &page     = dblwr_page->page;
-    page.check_sum = (CheckSum)-1;
+    auto  dblwr_page = make_unique<DoubleWritePage>();
+    Page &page       = dblwr_page->page;
+    page.check_sum   = (CheckSum)-1;
 
     ret = readn(file_desc_, dblwr_page.get(), DoubleWritePage::SIZE);
     if (ret != 0) {
@@ -289,10 +290,7 @@ RC DiskDoubleWriteBuffer::load_pages()
   return RC::SUCCESS;
 }
 
-RC DiskDoubleWriteBuffer::recover()
-{
-  return flush_page();
-}
+RC DiskDoubleWriteBuffer::recover() { return flush_page(); }
 
 ////////////////////////////////////////////////////////////////
 RC VacuousDoubleWriteBuffer::add_page(DiskBufferPool *bp, PageNum page_num, Page &page)
@@ -300,3 +298,4 @@ RC VacuousDoubleWriteBuffer::add_page(DiskBufferPool *bp, PageNum page_num, Page
   return bp->write_page(page_num, page);
 }
 
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/double_write_buffer.h b/src/observer/storage/buffer/double_write_buffer.h
index ce42c96a5..9d373f1ab 100644
--- a/src/observer/storage/buffer/double_write_buffer.h
+++ b/src/observer/storage/buffer/double_write_buffer.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "storage/buffer/page.h"
 
+namespace oceanbase {
+
 class DiskBufferPool;
 struct DoubleWritePage;
 class BufferPoolManager;
@@ -167,3 +169,4 @@ class VacuousDoubleWriteBuffer : public DoubleWriteBuffer
    */
   RC clear_pages(DiskBufferPool *bp) override { return RC::SUCCESS; }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/frame.cpp b/src/observer/storage/buffer/frame.cpp
index c61972e3a..d99ea076a 100644
--- a/src/observer/storage/buffer/frame.cpp
+++ b/src/observer/storage/buffer/frame.cpp
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "session/session.h"
 #include "session/thread_data.h"
 
+namespace oceanbase {
+
 FrameId::FrameId(int buffer_pool_id, PageNum page_num) : buffer_pool_id_(buffer_pool_id), page_num_(page_num) {}
 
 bool FrameId::equal_to(const FrameId &other) const
@@ -81,7 +83,13 @@ void Frame::write_latch(intptr_t xid)
   ++write_recursive_count_;
   TRACE("frame write lock success."
         "this=%p, pin=%d, frameId=%s, write locker=%lx(recursive=%d), xid=%lx, lbt=%s",
-        this, pin_count_.load(), frame_id_.to_string().c_str(), write_locker_, write_recursive_count_, xid, lbt());
+      this,
+      pin_count_.load(),
+      frame_id_.to_string().c_str(),
+      write_locker_,
+      write_recursive_count_,
+      xid,
+      lbt());
 #endif
 }
 
@@ -103,7 +111,11 @@ void Frame::write_unlatch(intptr_t xid)
       write_locker_, this, pin_count_.load(), frame_id_.to_string().c_str(), xid, lbt());
 
   TRACE("frame write unlock success. this=%p, pin=%d, frameId=%s, xid=%lx, lbt=%s",
-        this, pin_count_.load(), frame_id_.to_string().c_str(), xid, lbt());
+      this,
+      pin_count_.load(),
+      frame_id_.to_string().c_str(),
+      xid,
+      lbt());
 
   if (--write_recursive_count_ == 0) {
     write_locker_ = 0;
@@ -138,7 +150,12 @@ void Frame::read_latch(intptr_t xid)
     ++read_lockers_[xid];
     TRACE("frame read lock success."
           "this=%p, pin=%d, frameId=%s, xid=%lx, recursive=%d, lbt=%s",
-          this, pin_count_.load(), frame_id_.to_string().c_str(), xid, read_lockers_[xid], lbt());
+        this,
+        pin_count_.load(),
+        frame_id_.to_string().c_str(),
+        xid,
+        read_lockers_[xid],
+        lbt());
 #endif
   }
 }
@@ -166,7 +183,12 @@ bool Frame::try_read_latch()
     ++read_lockers_[xid];
     TRACE("frame read lock success."
           "this=%p, pin=%d, frameId=%s, xid=%lx, recursive=%d, lbt=%s",
-          this, pin_count_.load(), frame_id_.to_string().c_str(), xid, read_lockers_[xid], lbt());
+        this,
+        pin_count_.load(),
+        frame_id_.to_string().c_str(),
+        xid,
+        read_lockers_[xid],
+        lbt());
     debug_lock_.unlock();
 #endif
   }
@@ -203,7 +225,11 @@ void Frame::read_unlatch(intptr_t xid)
 
   TRACE("frame read unlock success."
         "this=%p, pin=%d, frameId=%s, xid=%lx, lbt=%s",
-        this, pin_count_.load(), frame_id_.to_string().c_str(), xid, lbt());
+      this,
+      pin_count_.load(),
+      frame_id_.to_string().c_str(),
+      xid,
+      lbt());
 
   lock_.unlock_shared();
 }
@@ -217,8 +243,13 @@ void Frame::pin()
 
   TRACE("after frame pin. "
         "this=%p, write locker=%lx, read locker has xid %d? pin=%d, frameId=%s, xid=%lx, lbt=%s",
-        this, write_locker_, read_lockers_.find(xid) != read_lockers_.end(), 
-        pin_count, frame_id_.to_string().c_str(), xid, lbt());
+      this,
+      write_locker_,
+      read_lockers_.find(xid) != read_lockers_.end(),
+      pin_count,
+      frame_id_.to_string().c_str(),
+      xid,
+      lbt());
 }
 
 int Frame::unpin()
@@ -235,8 +266,13 @@ int Frame::unpin()
   int pin_count = --pin_count_;
   TRACE("after frame unpin. "
         "this=%p, write locker=%lx, read locker has xid? %d, pin=%d, frameId=%s, xid=%lx, lbt=%s",
-        this, write_locker_, read_lockers_.find(xid) != read_lockers_.end(), 
-        pin_count, frame_id_.to_string().c_str(), xid, lbt());
+      this,
+      write_locker_,
+      read_lockers_.find(xid) != read_lockers_.end(),
+      pin_count,
+      frame_id_.to_string().c_str(),
+      xid,
+      lbt());
 
   if (0 == pin_count) {
     ASSERT(write_locker_ == 0,
@@ -261,7 +297,8 @@ void Frame::access() { acc_time_ = current_time(); }
 string Frame::to_string() const
 {
   stringstream ss;
-  ss << "frame id:" << frame_id().to_string() << ", dirty=" << dirty() << ", pin=" << pin_count()
-     << ", lsn=" << lsn() << ", this=" << this;
+  ss << "frame id:" << frame_id().to_string() << ", dirty=" << dirty() << ", pin=" << pin_count() << ", lsn=" << lsn()
+     << ", this=" << this;
   return ss.str();
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/frame.h b/src/observer/storage/buffer/frame.h
index 2c2e7d182..ceeb9b137 100644
--- a/src/observer/storage/buffer/frame.h
+++ b/src/observer/storage/buffer/frame.h
@@ -25,6 +25,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/types.h"
 #include "storage/buffer/page.h"
 
+namespace oceanbase {
+
 /**
  * @brief 页帧标识符
  * @ingroup BufferPool
@@ -187,3 +189,4 @@ class Frame
   int                          write_recursive_count_ = 0;
   unordered_map<intptr_t, int> read_lockers_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/buffer/page.h b/src/observer/storage/buffer/page.h
index cc7b02293..d0de43743 100644
--- a/src/observer/storage/buffer/page.h
+++ b/src/observer/storage/buffer/page.h
@@ -26,6 +26,8 @@ static constexpr PageNum BP_HEADER_PAGE = 0;
 static constexpr const int BP_PAGE_SIZE      = (1 << 13);
 static constexpr const int BP_PAGE_DATA_SIZE = (BP_PAGE_SIZE - sizeof(LSN) - sizeof(CheckSum));
 
+namespace oceanbase {
+
 /**
  * @brief 表示一个页面，可能放在内存或磁盘上
  * @ingroup BufferPool
@@ -36,3 +38,4 @@ struct Page
   CheckSum check_sum;
   char     data[BP_PAGE_DATA_SIZE];
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/disk_log_handler.cpp b/src/observer/storage/clog/disk_log_handler.cpp
index fdce4672f..5c64efc80 100644
--- a/src/observer/storage/clog/disk_log_handler.cpp
+++ b/src/observer/storage/clog/disk_log_handler.cpp
@@ -23,6 +23,8 @@ using namespace common;
 ////////////////////////////////////////////////////////////////////////////////
 // LogHandler
 
+namespace oceanbase {
+
 RC DiskLogHandler::init(const char *path)
 {
   const int max_entry_number_per_file = 1000;
@@ -75,7 +77,7 @@ RC DiskLogHandler::await_termination()
 
 RC DiskLogHandler::replay(LogReplayer &replayer, LSN start_lsn)
 {
-  LSN max_lsn = 0;
+  LSN  max_lsn         = 0;
   auto replay_callback = [&replayer, &max_lsn](LogEntry &entry) -> RC {
     if (entry.lsn() > max_lsn) {
       max_lsn = entry.lsn();
@@ -99,10 +101,10 @@ RC DiskLogHandler::replay(LogReplayer &replayer, LSN start_lsn)
   return rc;
 }
 
-RC DiskLogHandler::iterate(function<RC(LogEntry&)> consumer, LSN start_lsn)
+RC DiskLogHandler::iterate(function<RC(LogEntry &)> consumer, LSN start_lsn)
 {
   vector<string> log_files;
-  RC rc = file_manager_.list_files(log_files, start_lsn);
+  RC             rc = file_manager_.list_files(log_files, start_lsn);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to list clog files. rc=%s", strrc(rc));
     return rc;
@@ -172,7 +174,7 @@ void DiskLogHandler::thread_func()
   LOG_INFO("log handler thread started");
 
   LogFileWriter file_writer;
-  
+
   RC rc = RC::SUCCESS;
   while (running_.load() || entry_buffer_.entry_number() > 0) {
     if (!file_writer.valid() || rc == RC::LOG_FILE_FULL) {
@@ -193,7 +195,7 @@ void DiskLogHandler::thread_func()
     }
 
     int flush_count = 0;
-    rc = entry_buffer_.flush(file_writer, flush_count);
+    rc              = entry_buffer_.flush(file_writer, flush_count);
     if (OB_FAIL(rc) && RC::LOG_FILE_FULL != rc) {
       LOG_WARN("failed to flush log entry buffer. rc=%s", strrc(rc));
     }
@@ -206,3 +208,4 @@ void DiskLogHandler::thread_func()
 
   LOG_INFO("log handler thread stopped");
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/disk_log_handler.h b/src/observer/storage/clog/disk_log_handler.h
index ff378df2d..369fcba95 100644
--- a/src/observer/storage/clog/disk_log_handler.h
+++ b/src/observer/storage/clog/disk_log_handler.h
@@ -25,6 +25,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/log_buffer.h"
 #include "storage/clog/log_handler.h"
 
+namespace oceanbase {
+
 class LogReplayer;
 
 /**
@@ -127,3 +129,4 @@ class DiskLogHandler : public LogHandler
 
   string path_;  /// 日志文件存放的目录
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/integrated_log_replayer.cpp b/src/observer/storage/clog/integrated_log_replayer.cpp
index 008fa14ff..a50f7a24a 100644
--- a/src/observer/storage/clog/integrated_log_replayer.cpp
+++ b/src/observer/storage/clog/integrated_log_replayer.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/integrated_log_replayer.h"
 #include "storage/clog/log_entry.h"
 
+namespace oceanbase {
+
 IntegratedLogReplayer::IntegratedLogReplayer(BufferPoolManager &bpm)
     : buffer_pool_log_replayer_(bpm),
       record_log_replayer_(bpm),
@@ -66,4 +68,5 @@ RC IntegratedLogReplayer::on_done()
   }
 
   return RC::SUCCESS;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/integrated_log_replayer.h b/src/observer/storage/clog/integrated_log_replayer.h
index a281839c1..7b4883739 100644
--- a/src/observer/storage/clog/integrated_log_replayer.h
+++ b/src/observer/storage/clog/integrated_log_replayer.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/index/bplus_tree_log.h"
 #include "storage/trx/mvcc_trx_log.h"
 
+namespace oceanbase {
+
 class BufferPoolManager;
 
 /**
@@ -57,4 +59,5 @@ class IntegratedLogReplayer : public LogReplayer
   RecordLogReplayer       record_log_replayer_;       ///< record manager 日志回放器
   BplusTreeLogReplayer    bplus_tree_log_replayer_;   ///< bplus tree 日志回放器
   unique_ptr<LogReplayer> trx_log_replayer_;          ///< trx 日志回放器
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_buffer.cpp b/src/observer/storage/clog/log_buffer.cpp
index 4cbb10604..335d62174 100644
--- a/src/observer/storage/clog/log_buffer.cpp
+++ b/src/observer/storage/clog/log_buffer.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC LogEntryBuffer::init(LSN lsn, int32_t max_bytes /*= 0*/)
 {
   current_lsn_.store(lsn);
@@ -44,7 +46,7 @@ RC LogEntryBuffer::append(LSN &lsn, LogModule module, vector<char> &&data)
   }
 
   LogEntry entry;
-  RC rc = entry.init(lsn, module, std::move(data));
+  RC       rc = entry.init(lsn, module, std::move(data));
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to init log entry. rc=%s", strrc(rc));
     return rc;
@@ -78,7 +80,7 @@ RC LogEntryBuffer::flush(LogFileWriter &writer, int &count)
       entries_.pop_front();
       bytes_ -= entry.total_size();
     }
-    
+
     RC rc = writer.write(entry);
     if (OB_FAIL(rc)) {
       lock_guard guard(mutex_);
@@ -91,16 +93,11 @@ RC LogEntryBuffer::flush(LogFileWriter &writer, int &count)
       flushed_lsn_ = entry.lsn();
     }
   }
-  
+
   return RC::SUCCESS;
 }
 
-int64_t LogEntryBuffer::bytes() const
-{
-  return bytes_.load();
-}
+int64_t LogEntryBuffer::bytes() const { return bytes_.load(); }
 
-int32_t LogEntryBuffer::entry_number() const
-{
-  return entries_.size();
-}
+int32_t LogEntryBuffer::entry_number() const { return entries_.size(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_buffer.h b/src/observer/storage/clog/log_buffer.h
index 815af9144..2cc731a1e 100644
--- a/src/observer/storage/clog/log_buffer.h
+++ b/src/observer/storage/clog/log_buffer.h
@@ -23,6 +23,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/log_module.h"
 #include "storage/clog/log_entry.h"
 
+namespace oceanbase {
+
 class LogFileWriter;
 
 /**
@@ -68,7 +70,7 @@ class LogEntryBuffer
   LSN flushed_lsn() const { return flushed_lsn_.load(); }
 
 private:
-  mutex           mutex_;  /// 当前数据结构一定会在多线程中访问，所以强制使用有效的锁，而不是有条件生效的common::Mutex
+  mutex mutex_;    /// 当前数据结构一定会在多线程中访问，所以强制使用有效的锁，而不是有条件生效的common::Mutex
   deque<LogEntry> entries_;  /// 日志缓冲区
   atomic<int64_t> bytes_;    /// 当前缓冲区中的日志数据大小
 
@@ -77,3 +79,4 @@ class LogEntryBuffer
 
   int32_t max_bytes_ = 4 * 1024 * 1024;  /// 缓冲区最大字节数
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_entry.cpp b/src/observer/storage/clog/log_entry.cpp
index 0fbf27882..7d528a002 100644
--- a/src/observer/storage/clog/log_entry.cpp
+++ b/src/observer/storage/clog/log_entry.cpp
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/log_entry.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 ////////////////////////////////////////////////////////////////////////////////
 // struct LogHeader
 
@@ -23,9 +25,7 @@ const int32_t LogHeader::SIZE = sizeof(LogHeader);
 string LogHeader::to_string() const
 {
   stringstream ss;
-  ss << "lsn=" << lsn 
-     << ", size=" << size 
-     << ", module_id=" << module_id << ":" << LogModule(module_id).name();
+  ss << "lsn=" << lsn << ", size=" << size << ", module_id=" << module_id << ":" << LogModule(module_id).name();
 
   return ss.str();
 }
@@ -34,16 +34,16 @@ string LogHeader::to_string() const
 // class LogEntry
 LogEntry::LogEntry()
 {
-  header_.lsn = 0;
+  header_.lsn  = 0;
   header_.size = 0;
 }
 
 LogEntry::LogEntry(LogEntry &&other)
 {
   header_ = other.header_;
-  data_ = std::move(other.data_);
+  data_   = std::move(other.data_);
 
-  other.header_.lsn = 0;
+  other.header_.lsn  = 0;
   other.header_.size = 0;
 }
 
@@ -54,9 +54,9 @@ LogEntry &LogEntry::operator=(LogEntry &&other)
   }
 
   header_ = other.header_;
-  data_ = std::move(other.data_);
+  data_   = std::move(other.data_);
 
-  other.header_.lsn = 0;
+  other.header_.lsn  = 0;
   other.header_.size = 0;
 
   return *this;
@@ -74,14 +74,12 @@ RC LogEntry::init(LSN lsn, LogModule module, vector<char> &&data)
     return RC::INVALID_ARGUMENT;
   }
 
-  header_.lsn = lsn;
+  header_.lsn       = lsn;
   header_.module_id = module.index();
-  header_.size = static_cast<int32_t>(data.size());
-  data_ = std::move(data);
+  header_.size      = static_cast<int32_t>(data.size());
+  data_             = std::move(data);
   return RC::SUCCESS;
 }
 
-string LogEntry::to_string() const
-{
-  return header_.to_string();
-}
+string LogEntry::to_string() const { return header_.to_string(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_entry.h b/src/observer/storage/clog/log_entry.h
index d4d2981a3..2cd3a607a 100644
--- a/src/observer/storage/clog/log_entry.h
+++ b/src/observer/storage/clog/log_entry.h
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "common/lang/memory.h"
 
+namespace oceanbase {
+
 /**
  * @brief 描述一条日志头
  * @ingroup CLog
@@ -87,3 +89,4 @@ class LogEntry
   LogHeader    header_;  /// 日志头
   vector<char> data_;    /// 日志数据
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_file.cpp b/src/observer/storage/clog/log_file.cpp
index c15d0ac14..6b39fc5ba 100644
--- a/src/observer/storage/clog/log_file.cpp
+++ b/src/observer/storage/clog/log_file.cpp
@@ -23,6 +23,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 RC LogFileReader::open(const char *filename)
 {
   filename_ = filename;
@@ -141,10 +143,7 @@ RC LogFileReader::skip_to(LSN start_lsn)
 }
 ////////////////////////////////////////////////////////////////////////////////
 // LogFileWriter
-LogFileWriter::~LogFileWriter()
-{
-  (void)this->close();
-}
+LogFileWriter::~LogFileWriter() { (void)this->close(); }
 
 RC LogFileWriter::open(const char *filename, int end_lsn)
 {
@@ -153,7 +152,7 @@ RC LogFileWriter::open(const char *filename, int end_lsn)
   }
 
   filename_ = filename;
-  end_lsn_ = end_lsn;
+  end_lsn_  = end_lsn;
 
   fd_ = ::open(filename, O_WRONLY | O_APPEND | O_CREAT | O_SYNC, 0644);
   if (fd_ < 0) {
@@ -214,27 +213,18 @@ RC LogFileWriter::write(LogEntry &entry)
   return RC::SUCCESS;
 }
 
-bool LogFileWriter::valid() const
-{
-  return fd_ >= 0;
-}
+bool LogFileWriter::valid() const { return fd_ >= 0; }
 
-bool LogFileWriter::full() const
-{
-  return last_lsn_ >= end_lsn_;
-}
+bool LogFileWriter::full() const { return last_lsn_ >= end_lsn_; }
 
-string LogFileWriter::to_string() const
-{
-  return filename_;
-}
+string LogFileWriter::to_string() const { return filename_; }
 
 ////////////////////////////////////////////////////////////////////////////////
 // LogFileManager
 
 RC LogFileManager::init(const char *directory, int max_entry_number_per_file)
 {
-  directory_ = filesystem::absolute(filesystem::path(directory));
+  directory_                 = filesystem::absolute(filesystem::path(directory));
   max_entry_number_per_file_ = max_entry_number_per_file;
 
   // 检查目录是否存在，不存在就创建出来
@@ -242,7 +232,7 @@ RC LogFileManager::init(const char *directory, int max_entry_number_per_file)
     LOG_INFO("directory is not exist. directory=%s", directory_.c_str());
 
     error_code ec;
-    bool ret = filesystem::create_directories(directory_, ec);
+    bool       ret = filesystem::create_directories(directory_, ec);
     if (!ret) {
       LOG_WARN("create directory failed. directory=%s, error=%s", directory_.c_str(), ec.message().c_str());
       return RC::FILE_CREATE;
@@ -256,8 +246,8 @@ RC LogFileManager::init(const char *directory, int max_entry_number_per_file)
     }
 
     string filename = dir_entry.path().filename().string();
-    LSN lsn = 0;
-    RC rc = get_lsn_from_filename(filename, lsn);
+    LSN    lsn      = 0;
+    RC     rc       = get_lsn_from_filename(filename, lsn);
     if (OB_FAIL(rc)) {
       LOG_TRACE("invalid log file name. filename=%s", filename.c_str());
       continue;
@@ -283,7 +273,8 @@ RC LogFileManager::get_lsn_from_filename(const string &filename, LSN &lsn)
     return RC::INVALID_ARGUMENT;
   }
 
-  string_view lsn_str(filename.data() + strlen(file_prefix_), filename.length() - strlen(file_suffix_) - strlen(file_prefix_));
+  string_view lsn_str(
+      filename.data() + strlen(file_prefix_), filename.length() - strlen(file_suffix_) - strlen(file_prefix_));
   from_chars_result result = from_chars(lsn_str.data(), lsn_str.data() + lsn_str.size(), lsn);
   if (result.ec != errc()) {
     LOG_TRACE("invalid log file name: cannot calc lsn. filename=%s, error=%s", 
@@ -318,8 +309,7 @@ RC LogFileManager::last_file(LogFileWriter &file_writer)
   file_writer.close();
 
   auto last_file_item = log_files_.rbegin();
-  return file_writer.open(last_file_item->second.c_str(), 
-                          last_file_item->first + max_entry_number_per_file_ - 1);
+  return file_writer.open(last_file_item->second.c_str(), last_file_item->first + max_entry_number_per_file_ - 1);
 }
 
 RC LogFileManager::next_file(LogFileWriter &file_writer)
@@ -331,9 +321,10 @@ RC LogFileManager::next_file(LogFileWriter &file_writer)
     lsn = log_files_.rbegin()->first + max_entry_number_per_file_;
   }
 
-  string filename = file_prefix_ + to_string(lsn) + file_suffix_;
+  string           filename  = file_prefix_ + to_string(lsn) + file_suffix_;
   filesystem::path file_path = directory_ / filename;
   log_files_.emplace(lsn, file_path);
 
   return file_writer.open(file_path.c_str(), lsn + max_entry_number_per_file_ - 1);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_file.h b/src/observer/storage/clog/log_file.h
index f5014d42c..77a107074 100644
--- a/src/observer/storage/clog/log_file.h
+++ b/src/observer/storage/clog/log_file.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/fstream.h"
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 class LogEntry;
 
 /**
@@ -153,3 +155,4 @@ class LogFileManager
 
   map<LSN, filesystem::path> log_files_;  /// 日志文件名和第一个LSN的映射
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_handler.cpp b/src/observer/storage/clog/log_handler.cpp
index 14c49a576..0770e2a74 100644
--- a/src/observer/storage/clog/log_handler.cpp
+++ b/src/observer/storage/clog/log_handler.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/disk_log_handler.h"
 #include "storage/clog/vacuous_log_handler.h"
 
+namespace oceanbase {
+
 RC LogHandler::append(LSN &lsn, LogModule::Id module, span<const char> data)
 {
   vector<char> data_vec(data.begin(), data.end());
@@ -44,4 +46,5 @@ RC LogHandler::create(const char *name, LogHandler *&log_handler)
     return RC::INVALID_ARGUMENT;
   }
   return RC::SUCCESS;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_handler.h b/src/observer/storage/clog/log_handler.h
index 141df1537..20a59ff6a 100644
--- a/src/observer/storage/clog/log_handler.h
+++ b/src/observer/storage/clog/log_handler.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "storage/clog/log_module.h"
 
+namespace oceanbase {
+
 /**
  * @defgroup CLog commit log/redo log
  */
@@ -105,3 +107,4 @@ class LogHandler
    */
   virtual RC _append(LSN &lsn, LogModule module, vector<char> &&data) = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_module.h b/src/observer/storage/clog/log_module.h
index 120617cde..e01ebeab6 100644
--- a/src/observer/storage/clog/log_module.h
+++ b/src/observer/storage/clog/log_module.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include <stdint.h>
 
+namespace oceanbase {
+
 /**
  * @brief 日志模块
  * @ingroup CLog
@@ -51,4 +53,5 @@ class LogModule
 
 private:
   Id id_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/log_replayer.h b/src/observer/storage/clog/log_replayer.h
index 6ef1292a2..57e83a714 100644
--- a/src/observer/storage/clog/log_replayer.h
+++ b/src/observer/storage/clog/log_replayer.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/sys/rc.h"
 
+namespace oceanbase {
+
 class LogEntry;
 
 /**
@@ -40,3 +42,4 @@ class LogReplayer
    */
   virtual RC on_done() { return RC::SUCCESS; }
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/clog/vacuous_log_handler.h b/src/observer/storage/clog/vacuous_log_handler.h
index dbc31c213..567234513 100644
--- a/src/observer/storage/clog/vacuous_log_handler.h
+++ b/src/observer/storage/clog/vacuous_log_handler.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/clog/log_handler.h"
 
+namespace oceanbase {
+
 /**
  * @brief VacuousLogHandler is a log handler implenmentation that do nothing in all methods.
  * It is used for testing.
@@ -44,4 +46,5 @@ class VacuousLogHandler : public LogHandler
     lsn = 0;
     return RC::SUCCESS;
   }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/arena_allocator.cpp b/src/observer/storage/common/arena_allocator.cpp
index 342392a00..36643304a 100644
--- a/src/observer/storage/common/arena_allocator.cpp
+++ b/src/observer/storage/common/arena_allocator.cpp
@@ -14,43 +14,46 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/common/arena_allocator.h"
 
+namespace oceanbase {
+
 static const int kBlockSize = 4096;
 
-Arena::Arena()
-    : alloc_ptr_(nullptr), alloc_bytes_remaining_(0), memory_usage_(0) {}
+Arena::Arena() : alloc_ptr_(nullptr), alloc_bytes_remaining_(0), memory_usage_(0) {}
 
-Arena::~Arena() {
+Arena::~Arena()
+{
   for (size_t i = 0; i < blocks_.size(); i++) {
     delete[] blocks_[i];
   }
 }
 
-char* Arena::AllocateFallback(size_t bytes) {
+char *Arena::AllocateFallback(size_t bytes)
+{
   if (bytes > kBlockSize / 4) {
     // Object is more than a quarter of our block size.  Allocate it separately
     // to avoid wasting too much space in leftover bytes.
-    char* result = AllocateNewBlock(bytes);
+    char *result = AllocateNewBlock(bytes);
     return result;
   }
 
   // We waste the remaining space in the current block.
-  alloc_ptr_ = AllocateNewBlock(kBlockSize);
+  alloc_ptr_             = AllocateNewBlock(kBlockSize);
   alloc_bytes_remaining_ = kBlockSize;
 
-  char* result = alloc_ptr_;
+  char *result = alloc_ptr_;
   alloc_ptr_ += bytes;
   alloc_bytes_remaining_ -= bytes;
   return result;
 }
 
-char* Arena::AllocateAligned(size_t bytes) {
-  const int align = (sizeof(void*) > 8) ? sizeof(void*) : 8;
-  static_assert((align & (align - 1)) == 0,
-                "Pointer size should be a power of 2");
+char *Arena::AllocateAligned(size_t bytes)
+{
+  const int align = (sizeof(void *) > 8) ? sizeof(void *) : 8;
+  static_assert((align & (align - 1)) == 0, "Pointer size should be a power of 2");
   size_t current_mod = reinterpret_cast<uintptr_t>(alloc_ptr_) & (align - 1);
-  size_t slop = (current_mod == 0 ? 0 : align - current_mod);
-  size_t needed = bytes + slop;
-  char* result;
+  size_t slop        = (current_mod == 0 ? 0 : align - current_mod);
+  size_t needed      = bytes + slop;
+  char  *result;
   if (needed <= alloc_bytes_remaining_) {
     result = alloc_ptr_ + slop;
     alloc_ptr_ += needed;
@@ -63,10 +66,11 @@ char* Arena::AllocateAligned(size_t bytes) {
   return result;
 }
 
-char* Arena::AllocateNewBlock(size_t block_bytes) {
-  char* result = new char[block_bytes];
+char *Arena::AllocateNewBlock(size_t block_bytes)
+{
+  char *result = new char[block_bytes];
   blocks_.push_back(result);
-  memory_usage_.fetch_add(block_bytes + sizeof(char*),
-                          std::memory_order_relaxed);
+  memory_usage_.fetch_add(block_bytes + sizeof(char *), std::memory_order_relaxed);
   return result;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/arena_allocator.h b/src/observer/storage/common/arena_allocator.h
index c9ad05d50..f405e66db 100644
--- a/src/observer/storage/common/arena_allocator.h
+++ b/src/observer/storage/common/arena_allocator.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include <cstdint>
 #include <vector>
 
+namespace oceanbase {
+
 class Arena
 {
 public:
@@ -72,3 +74,4 @@ inline char *Arena::Allocate(size_t bytes)
   }
   return AllocateFallback(bytes);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/chunk.cpp b/src/observer/storage/common/chunk.cpp
index 9c7d5bd9d..30a02a14f 100644
--- a/src/observer/storage/common/chunk.cpp
+++ b/src/observer/storage/common/chunk.cpp
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/common/chunk.h"
 
+namespace oceanbase {
+
 void Chunk::add_column(unique_ptr<Column> col, int col_id)
 {
   columns_.push_back(std::move(col));
@@ -57,4 +59,5 @@ void Chunk::reset()
 {
   columns_.clear();
   column_ids_.clear();
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/chunk.h b/src/observer/storage/common/chunk.h
index 71c53b541..544985a7b 100644
--- a/src/observer/storage/common/chunk.h
+++ b/src/observer/storage/common/chunk.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "storage/common/column.h"
 
+namespace oceanbase {
+
 /**
  * @brief A Chunk represents a set of columns.
  */
@@ -100,3 +102,4 @@ class Chunk
   // `columnd_ids` store the ids of child operator that need to be output
   vector<int> column_ids_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/codec.cpp b/src/observer/storage/common/codec.cpp
index a8e363b00..093373c87 100644
--- a/src/observer/storage/common/codec.cpp
+++ b/src/observer/storage/common/codec.cpp
@@ -10,8 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/common/codec.h"
 
-const byte_t OrderedCode::term[] = {0x00, 0x01};
+const byte_t OrderedCode::term[]  = {0x00, 0x01};
 const byte_t OrderedCode::lit00[] = {0x00, 0xff};
 const byte_t OrderedCode::litff[] = {0xff, 0x00};
-const byte_t OrderedCode::inf[] = {0xff, 0xff};
-const byte_t OrderedCode::msb[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe};
\ No newline at end of file
+const byte_t OrderedCode::inf[]   = {0xff, 0xff};
+const byte_t OrderedCode::msb[]   = {0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe};
diff --git a/src/observer/storage/common/codec.h b/src/observer/storage/common/codec.h
index ed373de70..e1261b67d 100644
--- a/src/observer/storage/common/codec.h
+++ b/src/observer/storage/common/codec.h
@@ -24,6 +24,8 @@ using byte_t    = unsigned char;
 using bytes     = vector<byte_t>;
 using float64_t = double_t;
 
+namespace oceanbase {
+
 // reference: https://github.com/code0xff/orderedcodepp
 class OrderedCode
 {
@@ -503,3 +505,4 @@ class Codec
 //   }
 //   return rc;
 // }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/column.cpp b/src/observer/storage/common/column.cpp
index 3bea72665..9acc66eb5 100644
--- a/src/observer/storage/common/column.cpp
+++ b/src/observer/storage/common/column.cpp
@@ -11,6 +11,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "storage/common/column.h"
 
+namespace oceanbase {
+
 Column::Column(const FieldMeta &meta, size_t size)
     : data_(nullptr),
       count_(0),
@@ -21,16 +23,16 @@ Column::Column(const FieldMeta &meta, size_t size)
       column_type_(Type::NORMAL_COLUMN)
 {
   // TODO: optimized the memory usage if it doesn't need to allocate memory
-  data_     = new char[size * attr_len_];
+  data_ = new char[size * attr_len_];
   memset(data_, 0, size * attr_len_);
   capacity_ = size;
 }
 
 Column::Column(AttrType attr_type, int attr_len, size_t capacity)
 {
-  attr_type_   = attr_type;
-  attr_len_    = attr_len;
-  data_        = new char[capacity * attr_len_];
+  attr_type_ = attr_type;
+  attr_len_  = attr_len;
+  data_      = new char[capacity * attr_len_];
   memset(data_, 0, capacity * attr_len_);
   count_       = 0;
   capacity_    = capacity;
@@ -41,7 +43,7 @@ Column::Column(AttrType attr_type, int attr_len, size_t capacity)
 void Column::init(const FieldMeta &meta, size_t size)
 {
   reset();
-  data_        = new char[size * meta.len()];
+  data_ = new char[size * meta.len()];
   memset(data_, 0, size * meta.len());
   count_       = 0;
   capacity_    = size;
@@ -54,7 +56,7 @@ void Column::init(const FieldMeta &meta, size_t size)
 void Column::init(AttrType attr_type, int attr_len, size_t capacity)
 {
   reset();
-  data_        = new char[capacity * attr_len];
+  data_ = new char[capacity * attr_len];
   memset(data_, 0, capacity * attr_len);
   count_       = 0;
   capacity_    = capacity;
@@ -70,14 +72,14 @@ void Column::init(const Value &value, size_t size)
   attr_type_ = value.attr_type();
   attr_len_  = value.length();
   if (attr_len_ == 0) {
-    data_      = new char[1];
+    data_    = new char[1];
     data_[0] = '\0';
   } else {
-    data_      = new char[attr_len_];
+    data_ = new char[attr_len_];
   }
-  count_     = size;
-  capacity_  = 1;
-  own_       = true;
+  count_    = size;
+  capacity_ = 1;
+  own_      = true;
   memcpy(data_, value.data(), attr_len_);
   column_type_ = Type::CONSTANT_COLUMN;
 }
@@ -149,7 +151,7 @@ string_t Column::add_text(const char *data, int length)
 Value Column::get_value(int index) const
 {
   if (column_type_ == Type::CONSTANT_COLUMN) {
-    index  = 0;
+    index = 0;
   }
   if (index >= count_ || index < 0) {
     return Value();
@@ -173,3 +175,4 @@ void Column::reference(const Column &column)
   this->attr_type_   = column.attr_type();
   this->attr_len_    = column.attr_len();
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/column.h b/src/observer/storage/common/column.h
index 1eecba7ee..51b6e99ce 100644
--- a/src/observer/storage/common/column.h
+++ b/src/observer/storage/common/column.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/field/field_meta.h"
 #include "storage/common/vector_buffer.h"
 
+namespace oceanbase {
+
 /**
  * @brief A column contains multiple values in contiguous memory with a specified type.
  */
@@ -143,3 +145,4 @@ class Column
   Type                     column_type_   = Type::NORMAL_COLUMN;
   unique_ptr<VectorBuffer> vector_buffer_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/condition_filter.cpp b/src/observer/storage/common/condition_filter.cpp
index 5a62bb10f..2d1bb8d5e 100644
--- a/src/observer/storage/common/condition_filter.cpp
+++ b/src/observer/storage/common/condition_filter.cpp
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 ConditionFilter::~ConditionFilter() {}
 
 DefaultConditionFilter::DefaultConditionFilter()
@@ -211,3 +213,4 @@ bool CompositeConditionFilter::filter(const Record &rec) const
   }
   return true;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/condition_filter.h b/src/observer/storage/common/condition_filter.h
index 8fb4e5d18..e31d90dc6 100644
--- a/src/observer/storage/common/condition_filter.h
+++ b/src/observer/storage/common/condition_filter.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "sql/parser/parse.h"
 
+namespace oceanbase {
+
 class Record;
 class Table;
 
@@ -88,3 +90,4 @@ class CompositeConditionFilter : public ConditionFilter
   int                     filter_num_   = 0;
   bool                    memory_owner_ = false;  // filters_的内存是否由自己来控制
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/meta_util.cpp b/src/observer/storage/common/meta_util.cpp
index e11842d9a..5ad35da22 100644
--- a/src/observer/storage/common/meta_util.cpp
+++ b/src/observer/storage/common/meta_util.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/common/meta_util.h"
 #include "common/lang/filesystem.h"
 
+namespace oceanbase {
+
 string db_meta_file(const char *base_dir, const char *db_name)
 {
   filesystem::path db_dir = filesystem::path(base_dir);
@@ -38,4 +40,5 @@ string table_index_file(const char *base_dir, const char *table_name, const char
 string table_lob_file(const char *base_dir, const char *table_name)
 {
   return filesystem::path(base_dir) / (string(table_name) + TABLE_LOB_SUFFIX);
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/meta_util.h b/src/observer/storage/common/meta_util.h
index 0a299a3e1..e41c46700 100644
--- a/src/observer/storage/common/meta_util.h
+++ b/src/observer/storage/common/meta_util.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 static constexpr const char *DB_META_SUFFIX          = ".db";
 static constexpr const char *TABLE_META_SUFFIX       = ".table";
 static constexpr const char *TABLE_META_FILE_PATTERN = ".*\\.table$";
@@ -27,3 +29,4 @@ string table_meta_file(const char *base_dir, const char *table_name);
 string table_data_file(const char *base_dir, const char *table_name);
 string table_index_file(const char *base_dir, const char *table_name, const char *index_name);
 string table_lob_file(const char *base_dir, const char *table_name);
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/common/vector_buffer.h b/src/observer/storage/common/vector_buffer.h
index cfd33228f..a7987ea18 100644
--- a/src/observer/storage/common/vector_buffer.h
+++ b/src/observer/storage/common/vector_buffer.h
@@ -4,6 +4,8 @@
 #include "common/type/string_t.h"
 #include "common/log/log.h"
 
+namespace oceanbase {
+
 class VectorBuffer
 {
 public:
@@ -31,4 +33,5 @@ class VectorBuffer
 
 private:
   Arena heap;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/db/db.cpp b/src/observer/storage/db/db.cpp
index a0661fa00..0180598c1 100644
--- a/src/observer/storage/db/db.cpp
+++ b/src/observer/storage/db/db.cpp
@@ -30,6 +30,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 Db::~Db()
 {
   for (auto &iter : opened_tables_) {
@@ -49,7 +51,8 @@ Db::~Db()
   LOG_INFO("Db has been closed: %s", name_.c_str());
 }
 
-RC Db::init(const char *name, const char *dbpath, const char *trx_kit_name, const char *log_handler_name, const char *storage_engine)
+RC Db::init(const char *name, const char *dbpath, const char *trx_kit_name, const char *log_handler_name,
+    const char *storage_engine)
 {
   RC rc = RC::SUCCESS;
 
@@ -64,7 +67,7 @@ RC Db::init(const char *name, const char *dbpath, const char *trx_kit_name, cons
   }
 
   oceanbase::ObLsmOptions options;
-  filesystem::path lsm_path = filesystem::path(dbpath) / "lsm";
+  filesystem::path        lsm_path = filesystem::path(dbpath) / "lsm";
   filesystem::create_directory(lsm_path);
 
   rc = oceanbase::ObLsm::open(options, lsm_path, &lsm_);
@@ -150,7 +153,8 @@ RC Db::init(const char *name, const char *dbpath, const char *trx_kit_name, cons
   return rc;
 }
 
-RC Db::create_table(const char *table_name, span<const AttrInfoSqlNode> attributes, const vector<string>& primary_keys, const StorageFormat storage_format)
+RC Db::create_table(const char *table_name, span<const AttrInfoSqlNode> attributes, const vector<string> &primary_keys,
+    const StorageFormat storage_format)
 {
   RC rc = RC::SUCCESS;
   // check table_name
@@ -163,8 +167,15 @@ RC Db::create_table(const char *table_name, span<const AttrInfoSqlNode> attribut
   string  table_file_path = table_meta_file(path_.c_str(), table_name);
   Table  *table           = new Table();
   int32_t table_id        = next_table_id_++;
-  rc = table->create(this, table_id, table_file_path.c_str(), table_name, path_.c_str(), attributes, primary_keys, storage_format,
-                     get_storage_engine());
+  rc                      = table->create(this,
+      table_id,
+      table_file_path.c_str(),
+      table_name,
+      path_.c_str(),
+      attributes,
+      primary_keys,
+      storage_format,
+      get_storage_engine());
   if (rc != RC::SUCCESS) {
     LOG_ERROR("Failed to create table %s.", table_name);
     delete table;
@@ -415,3 +426,4 @@ RC Db::init_dblwr_buffer()
 LogHandler        &Db::log_handler() { return *log_handler_; }
 BufferPoolManager &Db::buffer_pool_manager() { return *buffer_pool_manager_; }
 TrxKit            &Db::trx_kit() { return *trx_kit_; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/db/db.h b/src/observer/storage/db/db.h
index 51afce10a..7cad886d1 100644
--- a/src/observer/storage/db/db.h
+++ b/src/observer/storage/db/db.h
@@ -26,6 +26,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/buffer/double_write_buffer.h"
 #include "oblsm/include/ob_lsm.h"
 
+namespace oceanbase {
+
 class Table;
 class LogHandler;
 class BufferPoolManager;
@@ -148,3 +150,4 @@ class Db
   LSN    check_point_lsn_ = 0;  ///< 当前数据库的检查点LSN。会记录到磁盘中。
   string storage_engine_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/default/default_handler.cpp b/src/observer/storage/default/default_handler.cpp
index 48f9e0098..7a513f34b 100644
--- a/src/observer/storage/default/default_handler.cpp
+++ b/src/observer/storage/default/default_handler.cpp
@@ -26,11 +26,14 @@ See the Mulan PSL v2 for more details. */
 
 using namespace std;
 
+namespace oceanbase {
+
 DefaultHandler::DefaultHandler() {}
 
 DefaultHandler::~DefaultHandler() noexcept { destroy(); }
 
-RC DefaultHandler::init(const char *base_dir, const char *trx_kit_name, const char *log_handler_name, const char *storage_engine)
+RC DefaultHandler::init(
+    const char *base_dir, const char *trx_kit_name, const char *log_handler_name, const char *storage_engine)
 {
   // 检查目录是否存在，或者创建
   filesystem::path db_dir(base_dir);
@@ -41,11 +44,11 @@ RC DefaultHandler::init(const char *base_dir, const char *trx_kit_name, const ch
     return RC::INTERNAL;
   }
 
-  base_dir_ = base_dir;
-  db_dir_   = db_dir;
-  trx_kit_name_ = trx_kit_name;
+  base_dir_         = base_dir;
+  db_dir_           = db_dir;
+  trx_kit_name_     = trx_kit_name;
   log_handler_name_ = log_handler_name;
-  storage_engine_ = storage_engine;
+  storage_engine_   = storage_engine;
 
   const char *sys_db = "sys";
 
@@ -121,7 +124,9 @@ RC DefaultHandler::open_db(const char *dbname)
   // open db
   Db *db  = new Db();
   RC  ret = RC::SUCCESS;
-  if ((ret = db->init(dbname, dbpath.c_str(), trx_kit_name_.c_str(), log_handler_name_.c_str(), storage_engine_.c_str())) != RC::SUCCESS) {
+  if ((ret = db->init(
+           dbname, dbpath.c_str(), trx_kit_name_.c_str(), log_handler_name_.c_str(), storage_engine_.c_str())) !=
+      RC::SUCCESS) {
     LOG_ERROR("Failed to open db: %s. error=%s", dbname, strrc(ret));
     delete db;
   } else {
@@ -180,3 +185,4 @@ RC DefaultHandler::sync()
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/default/default_handler.h b/src/observer/storage/default/default_handler.h
index c63119510..cb129bac9 100644
--- a/src/observer/storage/default/default_handler.h
+++ b/src/observer/storage/default/default_handler.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "common/lang/memory.h"
 
+namespace oceanbase {
+
 class Trx;
 class TrxKit;
 
@@ -98,3 +100,4 @@ class DefaultHandler
   map<string, Db *> opened_dbs_;        ///< 打开的数据库
   string            storage_engine_;    ///< 存储引擎的名称
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/field/field.cpp b/src/observer/storage/field/field.cpp
index b554787d8..934a05eff 100644
--- a/src/observer/storage/field/field.cpp
+++ b/src/observer/storage/field/field.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/value.h"
 #include "storage/record/record.h"
 
+namespace oceanbase {
+
 void Field::set_int(Record &record, int value)
 {
   ASSERT(field_->type() == AttrType::INTS, "could not set int value to a non-int field");
@@ -32,4 +34,5 @@ int Field::get_int(const Record &record)
   return value.get_int();
 }
 
-const char *Field::get_data(const Record &record) { return record.data() + field_->offset(); }
\ No newline at end of file
+const char *Field::get_data(const Record &record) { return record.data() + field_->offset(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/field/field.h b/src/observer/storage/field/field.h
index 7022eb5f1..ed279e375 100644
--- a/src/observer/storage/field/field.h
+++ b/src/observer/storage/field/field.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/field/field_meta.h"
 #include "storage/table/table.h"
 
+namespace oceanbase {
+
 /**
  * @brief 字段
  *
@@ -48,3 +50,4 @@ class Field
   const Table     *table_ = nullptr;
   const FieldMeta *field_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/field/field_meta.cpp b/src/observer/storage/field/field_meta.cpp
index 571861b69..2b509b0eb 100644
--- a/src/observer/storage/field/field_meta.cpp
+++ b/src/observer/storage/field/field_meta.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "json/json.h"
 
+namespace oceanbase {
+
 const static Json::StaticString FIELD_NAME("name");
 const static Json::StaticString FIELD_TYPE("type");
 const static Json::StaticString FIELD_OFFSET("offset");
@@ -26,7 +28,8 @@ const static Json::StaticString FIELD_LEN("len");
 const static Json::StaticString FIELD_VISIBLE("visible");
 const static Json::StaticString FIELD_FIELD_ID("FIELD_id");
 
-FieldMeta::FieldMeta() : attr_type_(AttrType::UNDEFINED), attr_offset_(-1), attr_len_(0), visible_(false), field_id_(0) {}
+FieldMeta::FieldMeta() : attr_type_(AttrType::UNDEFINED), attr_offset_(-1), attr_len_(0), visible_(false), field_id_(0)
+{}
 
 FieldMeta::FieldMeta(const char *name, AttrType attr_type, int attr_offset, int attr_len, bool visible, int field_id)
 {
@@ -52,7 +55,7 @@ RC FieldMeta::init(const char *name, AttrType attr_type, int attr_offset, int at
   attr_len_    = attr_len;
   attr_offset_ = attr_offset;
   visible_     = visible;
-  field_id_ = field_id;
+  field_id_    = field_id;
 
   LOG_INFO("Init a field with name=%s", name);
   return RC::SUCCESS;
@@ -78,11 +81,11 @@ void FieldMeta::desc(ostream &os) const
 
 void FieldMeta::to_json(Json::Value &json_value) const
 {
-  json_value[FIELD_NAME]    = name_;
-  json_value[FIELD_TYPE]    = attr_type_to_string(attr_type_);
-  json_value[FIELD_OFFSET]  = attr_offset_;
-  json_value[FIELD_LEN]     = attr_len_;
-  json_value[FIELD_VISIBLE] = visible_;
+  json_value[FIELD_NAME]     = name_;
+  json_value[FIELD_TYPE]     = attr_type_to_string(attr_type_);
+  json_value[FIELD_OFFSET]   = attr_offset_;
+  json_value[FIELD_LEN]      = attr_len_;
+  json_value[FIELD_VISIBLE]  = visible_;
   json_value[FIELD_FIELD_ID] = field_id_;
 }
 
@@ -93,11 +96,11 @@ RC FieldMeta::from_json(const Json::Value &json_value, FieldMeta &field)
     return RC::INTERNAL;
   }
 
-  const Json::Value &name_value    = json_value[FIELD_NAME];
-  const Json::Value &type_value    = json_value[FIELD_TYPE];
-  const Json::Value &offset_value  = json_value[FIELD_OFFSET];
-  const Json::Value &len_value     = json_value[FIELD_LEN];
-  const Json::Value &visible_value = json_value[FIELD_VISIBLE];
+  const Json::Value &name_value     = json_value[FIELD_NAME];
+  const Json::Value &type_value     = json_value[FIELD_TYPE];
+  const Json::Value &offset_value   = json_value[FIELD_OFFSET];
+  const Json::Value &len_value      = json_value[FIELD_LEN];
+  const Json::Value &visible_value  = json_value[FIELD_VISIBLE];
   const Json::Value &field_id_value = json_value[FIELD_FIELD_ID];
 
   if (!name_value.isString()) {
@@ -132,10 +135,11 @@ RC FieldMeta::from_json(const Json::Value &json_value, FieldMeta &field)
     return RC::INTERNAL;
   }
 
-  const char *name    = name_value.asCString();
-  int         offset  = offset_value.asInt();
-  int         len     = len_value.asInt();
-  bool        visible = visible_value.asBool();
-  int         field_id  = field_id_value.asInt();
+  const char *name     = name_value.asCString();
+  int         offset   = offset_value.asInt();
+  int         len      = len_value.asInt();
+  bool        visible  = visible_value.asBool();
+  int         field_id = field_id_value.asInt();
   return field.init(name, type, offset, len, visible, field_id);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/field/field_meta.h b/src/observer/storage/field/field_meta.h
index 2166b719f..7b4249f48 100644
--- a/src/observer/storage/field/field_meta.h
+++ b/src/observer/storage/field/field_meta.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "sql/parser/parse_defs.h"
 
+namespace oceanbase {
+
 namespace Json {
 class Value;
 }  // namespace Json
@@ -58,3 +60,4 @@ class FieldMeta
   bool     visible_;
   int      field_id_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree.cpp b/src/observer/storage/index/bplus_tree.cpp
index 606135ebc..7acb6d8fa 100644
--- a/src/observer/storage/index/bplus_tree.cpp
+++ b/src/observer/storage/index/bplus_tree.cpp
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 /**
  * @brief B+树的第一个页面存放的位置
  * @details B+树数据放到Buffer Pool中，Buffer Pool把文件按照固定大小的页面拆分。
@@ -77,15 +79,12 @@ int IndexNodeHandler::min_size() const
   return max - max / 2;
 }
 
-void IndexNodeHandler::increase_size(int n) 
-{
-  node_->key_num += n; 
-}
+void IndexNodeHandler::increase_size(int n) { node_->key_num += n; }
 
 PageNum IndexNodeHandler::parent_page_num() const { return node_->parent; }
 
-RC IndexNodeHandler::set_parent_page_num(PageNum page_num) 
-{ 
+RC IndexNodeHandler::set_parent_page_num(PageNum page_num)
+{
   RC rc = mtr_.logger().set_parent_page(*this, page_num, this->node_->parent);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log set parent page. rc=%s", strrc(rc));
@@ -192,20 +191,20 @@ RC LeafIndexNodeHandler::init_empty()
     LOG_WARN("failed to log init empty leaf node. rc=%s", strrc(rc));
     return rc;
   }
-  IndexNodeHandler::init_empty(true/*leaf*/);
+  IndexNodeHandler::init_empty(true /*leaf*/);
   leaf_node_->next_brother = BP_INVALID_PAGE_NUM;
   return RC::SUCCESS;
 }
 
-RC LeafIndexNodeHandler::set_next_page(PageNum page_num) 
-{ 
+RC LeafIndexNodeHandler::set_next_page(PageNum page_num)
+{
   RC rc = mtr_.logger().leaf_set_next_page(*this, page_num, leaf_node_->next_brother);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log set next page. rc=%s", strrc(rc));
     return rc;
   }
 
-  leaf_node_->next_brother = page_num; 
+  leaf_node_->next_brother = page_num;
   return RC::SUCCESS;
 }
 
@@ -275,13 +274,16 @@ int LeafIndexNodeHandler::remove(const char *key, const KeyComparator &comparato
 
 RC LeafIndexNodeHandler::move_half_to(LeafIndexNodeHandler &other)
 {
-  const int size       = this->size();
-  const int move_index = size / 2;
+  const int size          = this->size();
+  const int move_index    = size / 2;
   const int move_item_num = size - move_index;
 
   other.append(__item_at(move_index), move_item_num);
 
-  RC rc = mtr_.logger().node_remove_items(*this, move_index, span<const char>(__item_at(move_index), static_cast<size_t>(move_item_num) * item_size()), move_item_num);
+  RC rc = mtr_.logger().node_remove_items(*this,
+      move_index,
+      span<const char>(__item_at(move_index), static_cast<size_t>(move_item_num) * item_size()),
+      move_item_num);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log shrink leaf node. rc=%s", strrc(rc));
     return rc;
@@ -312,7 +314,10 @@ RC LeafIndexNodeHandler::move_to(LeafIndexNodeHandler &other)
   other.append(__item_at(0), this->size());
   other.set_next_page(this->next_page());
 
-  RC rc = mtr_.logger().node_remove_items(*this, 0, span<const char>(__item_at(0), static_cast<size_t>(this->size()) * static_cast<size_t>(item_size())), this->size());
+  RC rc = mtr_.logger().node_remove_items(*this,
+      0,
+      span<const char>(__item_at(0), static_cast<size_t>(this->size()) * static_cast<size_t>(item_size())),
+      this->size());
 
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log shrink leaf node. rc=%s", strrc(rc));
@@ -325,7 +330,8 @@ RC LeafIndexNodeHandler::move_to(LeafIndexNodeHandler &other)
 // 复制一些数据到当前节点的最右边
 RC LeafIndexNodeHandler::append(const char *items, int num)
 {
-  RC rc = mtr_.logger().node_insert_items(*this, size(), span<const char>(items, static_cast<size_t>(num) * static_cast<size_t>(item_size())), num);
+  RC rc = mtr_.logger().node_insert_items(
+      *this, size(), span<const char>(items, static_cast<size_t>(num) * static_cast<size_t>(item_size())), num);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log append items. rc=%d:%s", rc, strrc(rc));
     return rc;
@@ -334,15 +340,9 @@ RC LeafIndexNodeHandler::append(const char *items, int num)
   return recover_insert_items(size(), items, num);
 }
 
-RC LeafIndexNodeHandler::append(const char *item)
-{
-  return append(item, 1);
-}
+RC LeafIndexNodeHandler::append(const char *item) { return append(item, 1); }
 
-RC LeafIndexNodeHandler::preappend(const char *item)
-{
-  return insert(0, item, item + key_size());
-}
+RC LeafIndexNodeHandler::preappend(const char *item) { return insert(0, item, item + key_size()); }
 
 char *LeafIndexNodeHandler::__item_at(int index) const { return leaf_node_->array + (index * item_size()); }
 
@@ -380,7 +380,7 @@ bool LeafIndexNodeHandler::validate(const KeyComparator &comparator, DiskBufferP
   }
 
   Frame *parent_frame = nullptr;
-  RC     rc = bp->get_this_page(parent_page_num, &parent_frame);
+  RC     rc           = bp->get_this_page(parent_page_num, &parent_frame);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to fetch parent page. page num=%d, rc=%d:%s", parent_page_num, rc, strrc(rc));
     return false;
@@ -421,7 +421,8 @@ bool LeafIndexNodeHandler::validate(const KeyComparator &comparator, DiskBufferP
 }
 
 /////////////////////////////////////////////////////////////////////////////////
-InternalIndexNodeHandler::InternalIndexNodeHandler(BplusTreeMiniTransaction &mtr, const IndexFileHeader &header, Frame *frame)
+InternalIndexNodeHandler::InternalIndexNodeHandler(
+    BplusTreeMiniTransaction &mtr, const IndexFileHeader &header, Frame *frame)
     : IndexNodeHandler(mtr, header, frame), internal_node_((InternalIndexNode *)frame->data())
 {}
 
@@ -440,13 +441,13 @@ string to_string(const InternalIndexNodeHandler &node, const KeyPrinter &printer
   return ss.str();
 }
 
-RC InternalIndexNodeHandler::init_empty() 
+RC InternalIndexNodeHandler::init_empty()
 {
   RC rc = mtr_.logger().internal_init_empty(*this);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log init empty internal node. rc=%s", strrc(rc));
   }
-  IndexNodeHandler::init_empty(false/*leaf*/);
+  IndexNodeHandler::init_empty(false /*leaf*/);
   return RC::SUCCESS;
 }
 RC InternalIndexNodeHandler::create_new_root(PageNum first_page_num, const char *key, PageNum page_num)
@@ -501,7 +502,8 @@ RC InternalIndexNodeHandler::move_half_to(InternalIndexNodeHandler &other)
     return rc;
   }
 
-  mtr_.logger().node_remove_items(*this, move_index, span<const char>(__item_at(move_index), move_num * item_size()), move_num);
+  mtr_.logger().node_remove_items(
+      *this, move_index, span<const char>(__item_at(move_index), move_num * item_size()), move_num);
   increase_size(-(size - move_index));
   return rc;
 }
@@ -549,7 +551,8 @@ void InternalIndexNodeHandler::set_key_at(int index, const char *key)
 {
   assert(index >= 0 && index < size());
 
-  mtr_.logger().internal_update_key(*this, index, span<const char>(key, key_size()), span<const char>(__key_at(index), key_size()));
+  mtr_.logger().internal_update_key(
+      *this, index, span<const char>(key, key_size()), span<const char>(__key_at(index), key_size()));
   memcpy(__key_at(index), key, key_size());
 }
 
@@ -574,7 +577,7 @@ void InternalIndexNodeHandler::remove(int index)
   assert(index >= 0 && index < size());
 
   BplusTreeLogger &logger = mtr_.logger();
-  RC rc = logger.node_remove_items(*this, index, span<const char>(__item_at(index), item_size()), 1);
+  RC               rc     = logger.node_remove_items(*this, index, span<const char>(__item_at(index), item_size()), 1);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log remove item. rc=%s. node=%s", strrc(rc), to_string(*this).c_str());
   }
@@ -630,7 +633,8 @@ RC InternalIndexNodeHandler::move_last_to_front(InternalIndexNodeHandler &other)
 
 RC InternalIndexNodeHandler::insert_items(int index, const char *items, int num)
 {
-  RC rc = mtr_.logger().node_insert_items(*this, index, span<const char>(items, static_cast<size_t>(item_size()) * static_cast<size_t>(num)), num);
+  RC rc = mtr_.logger().node_insert_items(
+      *this, index, span<const char>(items, static_cast<size_t>(item_size()) * static_cast<size_t>(num)), num);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to log insert item. rc=%s", strrc(rc));
     return rc;
@@ -638,22 +642,22 @@ RC InternalIndexNodeHandler::insert_items(int index, const char *items, int num)
 
   recover_insert_items(index, items, num);
 
-  LatchMemo &latch_memo = mtr_.latch_memo();
-  PageNum this_page_num = this->page_num();
-  Frame *frame = nullptr;
+  LatchMemo &latch_memo    = mtr_.latch_memo();
+  PageNum    this_page_num = this->page_num();
+  Frame     *frame         = nullptr;
 
   // 设置所有页面的父页面为当前页面
   // 这里会访问大量的页面，可能会将他们从磁盘加载到内存中而占用大量的buffer pool页面
   for (int i = 0; i < num; i++) {
     const PageNum page_num = *(const PageNum *)((items + i * item_size()) + key_size());
-    rc = latch_memo.get_page(page_num, frame);
+    rc                     = latch_memo.get_page(page_num, frame);
     if (OB_FAIL(rc)) {
       LOG_WARN("failed to set child's page num. child page num:%d, this page num=%d, rc=%d:%s",
                page_num, this_page_num, rc, strrc(rc));
       return rc;
     }
     IndexNodeHandler child_node(mtr_, header_, frame);
-    child_node.set_parent_page_num(this_page_num); // 这里虽然对页面做了修改，但是并没有加写锁，因为父页面加了锁
+    child_node.set_parent_page_num(this_page_num);  // 这里虽然对页面做了修改，但是并没有加写锁，因为父页面加了锁
     frame->mark_dirty();
   }
 
@@ -663,17 +667,11 @@ RC InternalIndexNodeHandler::insert_items(int index, const char *items, int num)
 /**
  * copy items from other node to self's right
  */
-RC InternalIndexNodeHandler::append(const char *items, int num)
-{
-  return insert_items(size(), items, num);
-}
+RC InternalIndexNodeHandler::append(const char *items, int num) { return insert_items(size(), items, num); }
 
 RC InternalIndexNodeHandler::append(const char *item) { return this->append(item, 1); }
 
-RC InternalIndexNodeHandler::preappend(const char *item)
-{
-  return this->insert_items(0, item, 1);
-}
+RC InternalIndexNodeHandler::preappend(const char *item) { return this->insert_items(0, item, 1); }
 
 char *InternalIndexNodeHandler::__item_at(int index) const { return internal_node_->array + (index * item_size()); }
 
@@ -703,7 +701,7 @@ bool InternalIndexNodeHandler::validate(const KeyComparator &comparator, DiskBuf
       LOG_WARN("this page num=%d, got invalid child page. page num=%d", this->page_num(), page_num);
     } else {
       Frame *child_frame = nullptr;
-      RC     rc = bp->get_this_page(page_num, &child_frame);
+      RC     rc          = bp->get_this_page(page_num, &child_frame);
       if (OB_FAIL(rc)) {
         LOG_WARN("failed to fetch child page while validate internal page. page num=%d, rc=%d:%s", 
                  page_num, rc, strrc(rc));
@@ -729,7 +727,7 @@ bool InternalIndexNodeHandler::validate(const KeyComparator &comparator, DiskBuf
   }
 
   Frame *parent_frame = nullptr;
-  RC     rc = bp->get_this_page(parent_page_num, &parent_frame);
+  RC     rc           = bp->get_this_page(parent_page_num, &parent_frame);
   if (OB_FAIL(rc)) {
     LOG_WARN("failed to fetch parent page. page num=%d, rc=%d:%s", parent_page_num, rc, strrc(rc));
     return false;
@@ -793,13 +791,8 @@ RC BplusTreeHandler::sync()
   return disk_buffer_pool_->flush_all_pages();
 }
 
-RC BplusTreeHandler::create(LogHandler &log_handler,
-                            BufferPoolManager &bpm,
-                            const char *file_name, 
-                            AttrType attr_type, 
-                            int attr_length, 
-                            int internal_max_size /* = -1*/,
-                            int leaf_max_size /* = -1 */)
+RC BplusTreeHandler::create(LogHandler &log_handler, BufferPoolManager &bpm, const char *file_name, AttrType attr_type,
+    int attr_length, int internal_max_size /* = -1*/, int leaf_max_size /* = -1 */)
 {
   RC rc = bpm.create_file(file_name);
   if (OB_FAIL(rc)) {
@@ -827,12 +820,8 @@ RC BplusTreeHandler::create(LogHandler &log_handler,
   return rc;
 }
 
-RC BplusTreeHandler::create(LogHandler &log_handler,
-            DiskBufferPool &buffer_pool,
-            AttrType attr_type,
-            int attr_length,
-            int internal_max_size /* = -1 */,
-            int leaf_max_size /* = -1 */)
+RC BplusTreeHandler::create(LogHandler &log_handler, DiskBufferPool &buffer_pool, AttrType attr_type, int attr_length,
+    int internal_max_size /* = -1 */, int leaf_max_size /* = -1 */)
 {
   if (internal_max_size < 0) {
     internal_max_size = calc_internal_page_capacity(attr_length);
@@ -911,7 +900,7 @@ RC BplusTreeHandler::open(LogHandler &log_handler, BufferPoolManager &bpm, const
     return RC::RECORD_OPENNED;
   }
 
-  DiskBufferPool    *disk_buffer_pool = nullptr;
+  DiskBufferPool *disk_buffer_pool = nullptr;
 
   RC rc = bpm.open_file(log_handler, file_name, disk_buffer_pool);
   if (OB_FAIL(rc)) {
@@ -977,7 +966,7 @@ RC BplusTreeHandler::close()
 RC BplusTreeHandler::print_leaf(Frame *frame)
 {
   BplusTreeMiniTransaction mtr(*this);
-  LeafIndexNodeHandler leaf_node(mtr, file_header_, frame);
+  LeafIndexNodeHandler     leaf_node(mtr, file_header_, frame);
   LOG_INFO("leaf node: %s", to_string(leaf_node, key_printer_).c_str());
   disk_buffer_pool_->unpin_page(frame);
   return RC::SUCCESS;
@@ -985,7 +974,7 @@ RC BplusTreeHandler::print_leaf(Frame *frame)
 
 RC BplusTreeHandler::print_internal_node_recursive(Frame *frame)
 {
-  RC rc = RC::SUCCESS;
+  RC                       rc = RC::SUCCESS;
   BplusTreeMiniTransaction mtr(*this);
 
   LOG_INFO("bplus tree. file header: %s", file_header_.to_string().c_str());
@@ -1059,8 +1048,8 @@ RC BplusTreeHandler::print_leafs()
   }
 
   BplusTreeMiniTransaction mtr(*this);
-  LatchMemo latch_memo = mtr.latch_memo();
-  Frame    *frame = nullptr;
+  LatchMemo                latch_memo = mtr.latch_memo();
+  Frame                   *frame      = nullptr;
 
   RC rc = left_most_page(mtr, frame);
   if (OB_FAIL(rc)) {
@@ -1099,9 +1088,9 @@ bool BplusTreeHandler::validate_node_recursive(BplusTreeMiniTransaction &mtr, Fr
     InternalIndexNodeHandler internal_node(mtr, file_header_, frame);
     result = internal_node.validate(key_comparator_, disk_buffer_pool_);
     for (int i = 0; result && i < internal_node.size(); i++) {
-      PageNum page_num = internal_node.value_at(i);
+      PageNum page_num    = internal_node.value_at(i);
       Frame  *child_frame = nullptr;
-      RC      rc = mtr.latch_memo().get_page(page_num, child_frame);
+      RC      rc          = mtr.latch_memo().get_page(page_num, child_frame);
       if (OB_FAIL(rc)) {
         LOG_WARN("failed to fetch child page.page id=%d, rc=%d:%s", page_num, rc, strrc(rc));
         result = false;
@@ -1164,8 +1153,8 @@ bool BplusTreeHandler::validate_tree()
   }
 
   BplusTreeMiniTransaction mtr(*this);
-  LatchMemo &latch_memo = mtr.latch_memo();
-  Frame    *frame = nullptr;
+  LatchMemo               &latch_memo = mtr.latch_memo();
+  Frame                   *frame      = nullptr;
 
   RC rc = latch_memo.get_page(file_header_.root_page, frame);  // 这里仅仅调试使用，不加root锁
   if (OB_FAIL(rc)) {
@@ -1241,8 +1230,8 @@ RC BplusTreeHandler::crabing_protocal_fetch_page(
     BplusTreeMiniTransaction &mtr, BplusTreeOperationType op, PageNum page_num, bool is_root_node, Frame *&frame)
 {
   LatchMemo &latch_memo = mtr.latch_memo();
-  bool      readonly   = (op == BplusTreeOperationType::READ);
-  const int memo_point = latch_memo.memo_point();
+  bool       readonly   = (op == BplusTreeOperationType::READ);
+  const int  memo_point = latch_memo.memo_point();
 
   RC rc = latch_memo.get_page(page_num, frame);
   if (OB_FAIL(rc)) {
@@ -1259,7 +1248,8 @@ RC BplusTreeHandler::crabing_protocal_fetch_page(
   return rc;
 }
 
-RC BplusTreeHandler::insert_entry_into_leaf_node(BplusTreeMiniTransaction &mtr, Frame *frame, const char *key, const RID *rid)
+RC BplusTreeHandler::insert_entry_into_leaf_node(
+    BplusTreeMiniTransaction &mtr, Frame *frame, const char *key, const RID *rid)
 {
   LeafIndexNodeHandler leaf_node(mtr, file_header_, frame);
   bool                 exists          = false;  // 该数据是否已经存在指定的叶子节点中了
@@ -1297,7 +1287,8 @@ RC BplusTreeHandler::insert_entry_into_leaf_node(BplusTreeMiniTransaction &mtr,
   return insert_entry_into_parent(mtr, frame, new_frame, new_index_node.key_at(0));
 }
 
-RC BplusTreeHandler::insert_entry_into_parent(BplusTreeMiniTransaction &mtr, Frame *frame, Frame *new_frame, const char *key)
+RC BplusTreeHandler::insert_entry_into_parent(
+    BplusTreeMiniTransaction &mtr, Frame *frame, Frame *new_frame, const char *key)
 {
   RC rc = RC::SUCCESS;
 
@@ -1309,7 +1300,7 @@ RC BplusTreeHandler::insert_entry_into_parent(BplusTreeMiniTransaction &mtr, Fra
 
     // create new root page
     Frame *root_frame = nullptr;
-    rc = disk_buffer_pool_->allocate_page(&root_frame);
+    rc                = disk_buffer_pool_->allocate_page(&root_frame);
     if (OB_FAIL(rc)) {
       LOG_WARN("failed to allocate new root page. rc=%d:%s", rc, strrc(rc));
       return rc;
@@ -1429,11 +1420,12 @@ RC BplusTreeHandler::recover_update_root_page(BplusTreeMiniTransaction &mtr, Pag
   return RC::SUCCESS;
 }
 
-RC BplusTreeHandler::recover_init_header_page(BplusTreeMiniTransaction &mtr, Frame *frame, const IndexFileHeader &header)
+RC BplusTreeHandler::recover_init_header_page(
+    BplusTreeMiniTransaction &mtr, Frame *frame, const IndexFileHeader &header)
 {
   IndexFileHeader *file_header = reinterpret_cast<IndexFileHeader *>(frame->data());
   memcpy(file_header, &header, sizeof(IndexFileHeader));
-  file_header_ = header;
+  file_header_  = header;
   header_dirty_ = false;
   frame->mark_dirty();
 
@@ -1731,7 +1723,8 @@ RC BplusTreeHandler::coalesce(
 }
 
 template <typename IndexNodeHandlerType>
-RC BplusTreeHandler::redistribute(BplusTreeMiniTransaction &mtr, Frame *neighbor_frame, Frame *frame, Frame *parent_frame, int index)
+RC BplusTreeHandler::redistribute(
+    BplusTreeMiniTransaction &mtr, Frame *neighbor_frame, Frame *frame, Frame *parent_frame, int index)
 {
   InternalIndexNodeHandler parent_node(mtr, file_header_, parent_frame);
   IndexNodeHandlerType     neighbor_node(mtr, file_header_, neighbor_frame);
@@ -1820,9 +1813,7 @@ RC BplusTreeHandler::delete_entry(const char *user_key, const RID *rid)
 
 ////////////////////////////////////////////////////////////////////////////////
 
-BplusTreeScanner::BplusTreeScanner(BplusTreeHandler &tree_handler)
-    : tree_handler_(tree_handler), mtr_(tree_handler)
-{}
+BplusTreeScanner::BplusTreeScanner(BplusTreeHandler &tree_handler) : tree_handler_(tree_handler), mtr_(tree_handler) {}
 
 BplusTreeScanner::~BplusTreeScanner() { close(); }
 
@@ -1858,7 +1849,7 @@ RC BplusTreeScanner::open(const char *left_user_key, int left_len, bool left_inc
         current_frame_ = nullptr;
         return RC::SUCCESS;
       }
-      
+
       LOG_WARN("failed to find left most page. rc=%s", strrc(rc));
       return rc;
     }
@@ -2094,3 +2085,4 @@ RC BplusTreeScanner::fix_user_key(
   *fixed_key = key_buf;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree.h b/src/observer/storage/index/bplus_tree.h
index dd7520564..cd51492f5 100644
--- a/src/observer/storage/index/bplus_tree.h
+++ b/src/observer/storage/index/bplus_tree.h
@@ -30,6 +30,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/index/latch_memo.h"
 #include "storage/index/bplus_tree_log.h"
 
+namespace oceanbase {
+
 class BplusTreeHandler;
 class BplusTreeMiniTransaction;
 
@@ -721,3 +723,4 @@ class BplusTreeScanner
   int                                  iter_index_    = -1;
   bool                                 first_emitted_ = false;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree_index.cpp b/src/observer/storage/index/bplus_tree_index.cpp
index 8794cfbc1..90d1496e0 100644
--- a/src/observer/storage/index/bplus_tree_index.cpp
+++ b/src/observer/storage/index/bplus_tree_index.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/table/table.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
+
 BplusTreeIndex::~BplusTreeIndex() noexcept { close(); }
 
 RC BplusTreeIndex::create(Table *table, const char *file_name, const IndexMeta &index_meta, const FieldMeta &field_meta)
@@ -55,7 +57,7 @@ RC BplusTreeIndex::open(Table *table, const char *file_name, const IndexMeta &in
   Index::init(index_meta, field_meta);
 
   BufferPoolManager &bpm = table->db()->buffer_pool_manager();
-  RC rc = index_handler_.open(table->db()->log_handler(), bpm, file_name);
+  RC                 rc  = index_handler_.open(table->db()->log_handler(), bpm, file_name);
   if (RC::SUCCESS != rc) {
     LOG_WARN("Failed to open index_handler, file_name:%s, index:%s, field:%s, rc:%s",
         file_name, index_meta.name(), index_meta.field(), strrc(rc));
@@ -123,3 +125,4 @@ RC BplusTreeIndexScanner::destroy()
   delete this;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree_index.h b/src/observer/storage/index/bplus_tree_index.h
index db0bbc99b..e39f21a4c 100644
--- a/src/observer/storage/index/bplus_tree_index.h
+++ b/src/observer/storage/index/bplus_tree_index.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/index/bplus_tree.h"
 #include "storage/index/index.h"
 
+namespace oceanbase {
+
 /**
  * @brief B+树索引
  * @ingroup Index
@@ -67,3 +69,4 @@ class BplusTreeIndexScanner : public IndexScanner
 private:
   BplusTreeScanner tree_scanner_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree_log.cpp b/src/observer/storage/index/bplus_tree_log.cpp
index 2225a38e1..144343300 100644
--- a/src/observer/storage/index/bplus_tree_log.cpp
+++ b/src/observer/storage/index/bplus_tree_log.cpp
@@ -27,6 +27,8 @@ See the Mulan PSL v2 for more details. */
 using namespace common;
 using namespace bplus_tree;
 
+namespace oceanbase {
+
 ///////////////////////////////////////////////////////////////////////////////
 // class BplusTreeLogger
 BplusTreeLogger::BplusTreeLogger(LogHandler &log_handler, int32_t buffer_pool_id)
@@ -182,13 +184,14 @@ RC BplusTreeLogger::redo(BufferPoolManager &bpm, const LogEntry &entry)
   return rc;
 }
 
-RC BplusTreeLogger::__redo(LSN lsn, BplusTreeMiniTransaction &mtr, BplusTreeHandler &tree_handler, Deserializer &redo_buffer)
+RC BplusTreeLogger::__redo(
+    LSN lsn, BplusTreeMiniTransaction &mtr, BplusTreeHandler &tree_handler, Deserializer &redo_buffer)
 {
   need_log_ = false;
 
   DEFER(need_log_ = true);
 
-  RC rc = RC::SUCCESS;
+  RC              rc = RC::SUCCESS;
   vector<Frame *> frames;
   while (redo_buffer.remain() > 0) {
     unique_ptr<LogEntryHandler> entry;
@@ -202,8 +205,8 @@ RC BplusTreeLogger::__redo(LSN lsn, BplusTreeMiniTransaction &mtr, BplusTreeHand
     if (frame != nullptr) {
       if (frame->lsn() >= lsn) {
         LOG_TRACE("no need to redo. frame=%p:%s, redo lsn=%ld", frame, frame->to_string().c_str(), lsn);
-	frame->unpin();
-	continue;
+        frame->unpin();
+        continue;
       } else {
         frames.push_back(frame);
       }
@@ -273,7 +276,7 @@ BplusTreeMiniTransaction::~BplusTreeMiniTransaction()
   if (nullptr == operation_result_) {
     return;
   }
-  
+
   if (OB_SUCC(*operation_result_)) {
     commit();
   } else {
@@ -290,3 +293,4 @@ RC BplusTreeMiniTransaction::rollback() { return logger_.rollback(*this, tree_ha
 BplusTreeLogReplayer::BplusTreeLogReplayer(BufferPoolManager &bpm) : buffer_pool_manager_(bpm) {}
 
 RC BplusTreeLogReplayer::replay(const LogEntry &entry) { return BplusTreeLogger::redo(buffer_pool_manager_, entry); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree_log.h b/src/observer/storage/index/bplus_tree_log.h
index cb59bdf75..1d0a27942 100644
--- a/src/observer/storage/index/bplus_tree_log.h
+++ b/src/observer/storage/index/bplus_tree_log.h
@@ -26,6 +26,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/log_replayer.h"
 // #include "storage/index/bplus_tree_log_entry.h"
 
+namespace oceanbase {
+
 struct IndexFileHeader;
 class LogEntry;
 class LogHandler;
@@ -206,3 +208,4 @@ class BplusTreeLogReplayer final : public LogReplayer
 private:
   BufferPoolManager &buffer_pool_manager_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree_log_entry.cpp b/src/observer/storage/index/bplus_tree_log_entry.cpp
index 615bb52b4..547342ad2 100644
--- a/src/observer/storage/index/bplus_tree_log_entry.cpp
+++ b/src/observer/storage/index/bplus_tree_log_entry.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 namespace bplus_tree {
 
 string LogOperation::to_string() const
@@ -363,7 +365,7 @@ LeafInitEmptyLogEntryHandler::LeafInitEmptyLogEntryHandler(Frame *frame)
 RC LeafInitEmptyLogEntryHandler::redo(BplusTreeMiniTransaction &mtr, BplusTreeHandler &tree_handler)
 {
   LeafIndexNodeHandler leaf_handler(mtr, tree_handler.file_header(), frame());
-  RC rc = leaf_handler.init_empty();
+  RC                   rc = leaf_handler.init_empty();
   return rc;
 }
 
@@ -494,7 +496,7 @@ RC InternalCreateNewRootLogEntryHandler::deserialize(
 RC InternalCreateNewRootLogEntryHandler::redo(BplusTreeMiniTransaction &mtr, BplusTreeHandler &tree_handler)
 {
   InternalIndexNodeHandler internal_handler(mtr, tree_handler.file_header(), frame());
-  RC rc = internal_handler.create_new_root(first_page_num_, key_.data(), page_num_);
+  RC                       rc = internal_handler.create_new_root(first_page_num_, key_.data(), page_num_);
   return rc;
 }
 
@@ -606,3 +608,4 @@ RC UpdateRootPageLogEntryHandler::redo(BplusTreeMiniTransaction &mtr, BplusTreeH
 }
 
 }  // namespace bplus_tree
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/bplus_tree_log_entry.h b/src/observer/storage/index/bplus_tree_log_entry.h
index 7cdab743e..75739dfb4 100644
--- a/src/observer/storage/index/bplus_tree_log_entry.h
+++ b/src/observer/storage/index/bplus_tree_log_entry.h
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/string.h"
 #include "storage/index/bplus_tree.h"
 
+namespace oceanbase {
+
 class IndexNodeHandler;
 class BplusTreeHandler;
 class BplusTreeMiniTransaction;
@@ -377,3 +379,4 @@ class InternalUpdateKeyLogEntryHandler : public NodeLogEntryHandler
 };
 
 }  // namespace bplus_tree
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/index.cpp b/src/observer/storage/index/index.cpp
index 6fa51531d..ba332a61f 100644
--- a/src/observer/storage/index/index.cpp
+++ b/src/observer/storage/index/index.cpp
@@ -14,9 +14,12 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/index/index.h"
 
+namespace oceanbase {
+
 RC Index::init(const IndexMeta &index_meta, const FieldMeta &field_meta)
 {
   index_meta_ = index_meta;
   field_meta_ = field_meta;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/index.h b/src/observer/storage/index/index.h
index 67bfe9a55..becf2cd7d 100644
--- a/src/observer/storage/index/index.h
+++ b/src/observer/storage/index/index.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/index/index_meta.h"
 #include "storage/record/record_manager.h"
 
+namespace oceanbase {
+
 class IndexScanner;
 
 /**
@@ -113,3 +115,4 @@ class IndexScanner
   virtual RC next_entry(RID *rid) = 0;
   virtual RC destroy()            = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/index_meta.cpp b/src/observer/storage/index/index_meta.cpp
index 32604b9ff..0a3c30939 100644
--- a/src/observer/storage/index/index_meta.cpp
+++ b/src/observer/storage/index/index_meta.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/table/table_meta.h"
 #include "json/json.h"
 
+namespace oceanbase {
+
 const static Json::StaticString FIELD_NAME("name");
 const static Json::StaticString FIELD_FIELD_NAME("field_name");
 
@@ -68,4 +70,5 @@ const char *IndexMeta::name() const { return name_.c_str(); }
 
 const char *IndexMeta::field() const { return field_.c_str(); }
 
-void IndexMeta::desc(ostream &os) const { os << "index name=" << name_ << ", field=" << field_; }
\ No newline at end of file
+void IndexMeta::desc(ostream &os) const { os << "index name=" << name_ << ", field=" << field_; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/index_meta.h b/src/observer/storage/index/index_meta.h
index bb9f948b1..8ea300d5c 100644
--- a/src/observer/storage/index/index_meta.h
+++ b/src/observer/storage/index/index_meta.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 class TableMeta;
 class FieldMeta;
 
@@ -51,3 +53,4 @@ class IndexMeta
   string name_;   // index's name
   string field_;  // field's name
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/ivfflat_index.h b/src/observer/storage/index/ivfflat_index.h
index cb09f47ad..52c3a8d09 100644
--- a/src/observer/storage/index/ivfflat_index.h
+++ b/src/observer/storage/index/ivfflat_index.h
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/index/index.h"
 
+namespace oceanbase {
+
 /**
  * @brief ivfflat 向量索引
  * @ingroup Index
@@ -19,7 +21,7 @@ See the Mulan PSL v2 for more details. */
 class IvfflatIndex : public Index
 {
 public:
-  IvfflatIndex(){};
+  IvfflatIndex() {};
   virtual ~IvfflatIndex() noexcept {};
 
   RC create(Table *table, const char *file_name, const IndexMeta &index_meta, const FieldMeta &field_meta)
@@ -47,3 +49,4 @@ class IvfflatIndex : public Index
   int    lists_  = 1;
   int    probes_ = 1;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/latch_memo.cpp b/src/observer/storage/index/latch_memo.cpp
index 05158eda0..28e4b9e5e 100644
--- a/src/observer/storage/index/latch_memo.cpp
+++ b/src/observer/storage/index/latch_memo.cpp
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/buffer/disk_buffer_pool.h"
 #include "storage/buffer/frame.h"
 
+namespace oceanbase {
+
 LatchMemoItem::LatchMemoItem(LatchMemoType type, Frame *frame)
 {
   this->type  = type;
@@ -158,3 +160,4 @@ void LatchMemo::release_to(int point)
   }
   items_.erase(items_.begin(), iter);
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/index/latch_memo.h b/src/observer/storage/index/latch_memo.h
index b729db542..9c9132d08 100644
--- a/src/observer/storage/index/latch_memo.h
+++ b/src/observer/storage/index/latch_memo.h
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/vector.h"
 #include "storage/buffer/page.h"
 
+namespace oceanbase {
+
 class Frame;
 class DiskBufferPool;
 
@@ -88,3 +90,4 @@ class LatchMemo final
   deque<LatchMemoItem> items_;
   vector<PageNum>      disposed_pages_;  /// 等待释放的页面
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/persist/persist.cpp b/src/observer/storage/persist/persist.cpp
index 866a95878..81232b5f3 100644
--- a/src/observer/storage/persist/persist.cpp
+++ b/src/observer/storage/persist/persist.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/log/log.h"
 #include "persist.h"
 
+namespace oceanbase {
+
 PersistHandler::PersistHandler() {}
 
 PersistHandler::~PersistHandler() { close_file(); }
@@ -282,3 +284,4 @@ RC PersistHandler::seek(uint64_t offset)
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/persist/persist.h b/src/observer/storage/persist/persist.h
index 45f61f7dc..c3847fbc4 100644
--- a/src/observer/storage/persist/persist.h
+++ b/src/observer/storage/persist/persist.h
@@ -24,6 +24,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/sys/rc.h"
 #include "common/lang/string.h"
 
+namespace oceanbase {
+
 class PersistHandler
 {
 public:
@@ -64,3 +66,4 @@ class PersistHandler
   string file_name_;
   int    file_desc_ = -1;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/heap_record_scanner.cpp b/src/observer/storage/record/heap_record_scanner.cpp
index cc1182429..a5517b67e 100644
--- a/src/observer/storage/record/heap_record_scanner.cpp
+++ b/src/observer/storage/record/heap_record_scanner.cpp
@@ -12,6 +12,7 @@ See the Mulan PSL v2 for more details. */
 
 ////////////////////////////////////////////////////////////////////////////////
 
+namespace oceanbase {
 
 RC HeapRecordScanner::open_scan()
 {
@@ -145,3 +146,4 @@ RC HeapRecordScanner::next(Record &record)
   record = next_record_;
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/heap_record_scanner.h b/src/observer/storage/record/heap_record_scanner.h
index 2915eeaef..34f6b32e7 100644
--- a/src/observer/storage/record/heap_record_scanner.h
+++ b/src/observer/storage/record/heap_record_scanner.h
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/buffer/disk_buffer_pool.h"
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 /**
  * @brief 遍历某个文件中所有记录
  * @ingroup RecordManager
@@ -68,11 +70,12 @@ class HeapRecordScanner : public RecordScanner
   DiskBufferPool *disk_buffer_pool_ = nullptr;  ///< 当前访问的文件
   Trx            *trx_              = nullptr;  ///< 当前是哪个事务在遍历
   LogHandler     *log_handler_      = nullptr;
-  ReadWriteMode   rw_mode_ = ReadWriteMode::READ_WRITE;  ///< 遍历出来的数据，是否可能对它做修改
+  ReadWriteMode rw_mode_ = ReadWriteMode::READ_WRITE;  ///< 遍历出来的数据，是否可能对它做修改
 
   BufferPoolIterator bp_iterator_;                    ///< 遍历buffer pool的所有页面
   ConditionFilter   *condition_filter_    = nullptr;  ///< 过滤record
   RecordPageHandler *record_page_handler_ = nullptr;  ///< 处理文件某页面的记录
   RecordPageIterator record_page_iterator_;           ///< 遍历某个页面上的所有record
   Record             next_record_;                    ///< 获取的记录放在这里缓存起来
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/lob_handler.cpp b/src/observer/storage/record/lob_handler.cpp
index b7905170e..1a1284852 100644
--- a/src/observer/storage/record/lob_handler.cpp
+++ b/src/observer/storage/record/lob_handler.cpp
@@ -10,10 +10,9 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/record/lob_handler.h"
 
-RC LobFileHandler::create_file(const char *file_name)
-{
-  return file_.create_file(file_name);
-}
+namespace oceanbase {
+
+RC LobFileHandler::create_file(const char *file_name) { return file_.create_file(file_name); }
 
 RC LobFileHandler::open_file(const char *file_name)
 {
@@ -28,10 +27,10 @@ RC LobFileHandler::open_file(const char *file_name)
 
 RC LobFileHandler::insert_data(int64_t &offset, int64_t length, const char *data)
 {
-  RC       rc         = RC::SUCCESS;
-  int64_t  out_size   = 0;
+  RC      rc         = RC::SUCCESS;
+  int64_t out_size   = 0;
   int64_t end_offset = 0;
-  rc                  = file_.append(length, data, &out_size, &end_offset);
+  rc                 = file_.append(length, data, &out_size, &end_offset);
   if (OB_FAIL(rc)) {
     return rc;
   }
@@ -42,3 +41,4 @@ RC LobFileHandler::insert_data(int64_t &offset, int64_t length, const char *data
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/lob_handler.h b/src/observer/storage/record/lob_handler.h
index 99d86798a..3dd45676c 100644
--- a/src/observer/storage/record/lob_handler.h
+++ b/src/observer/storage/record/lob_handler.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/types.h"
 #include "storage/persist/persist.h"
 
+namespace oceanbase {
+
 /**
  * @brief 管理LOB文件中的 LOB 对象
  * @ingroup RecordManager
@@ -38,4 +40,5 @@ class LobFileHandler
 
 private:
   PersistHandler file_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/lsm_record_scanner.cpp b/src/observer/storage/record/lsm_record_scanner.cpp
index 59eef6850..6dc0ccf15 100644
--- a/src/observer/storage/record/lsm_record_scanner.cpp
+++ b/src/observer/storage/record/lsm_record_scanner.cpp
@@ -12,6 +12,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/common/codec.h"
 #include "storage/trx/lsm_mvcc_trx.h"
 
+namespace oceanbase {
+
 RC LsmRecordScanner::open_scan()
 {
   RC rc = RC::SUCCESS;
@@ -23,7 +25,7 @@ RC LsmRecordScanner::open_scan()
     lsm_iter_ = oblsm_->new_iterator(ObLsmReadOptions());
   } else if (trx_->type() == TrxKit::Type::LSM) {
     auto lsm_trx = dynamic_cast<LsmMvccTrx *>(trx_);
-    lsm_iter_ = lsm_trx->get_trx()->new_iterator(ObLsmReadOptions());
+    lsm_iter_    = lsm_trx->get_trx()->new_iterator(ObLsmReadOptions());
   }
   bytes encoded_key;
   rc = Codec::encode_without_rid(table_->table_id(), encoded_key);
@@ -36,7 +38,6 @@ RC LsmRecordScanner::open_scan()
   return rc;
 }
 
-
 RC LsmRecordScanner::close_scan()
 {
   if (lsm_iter_ != nullptr) {
@@ -50,9 +51,9 @@ RC LsmRecordScanner::next(Record &record)
 {
   if (lsm_iter_->valid()) {
     string_view lsm_value = lsm_iter_->value();
-    string_view lsm_key = lsm_iter_->key();
-    int64_t table_id = 0;
-    bytes lsm_key_bytes(lsm_key.begin(), lsm_key.end());
+    string_view lsm_key   = lsm_iter_->key();
+    int64_t     table_id  = 0;
+    bytes       lsm_key_bytes(lsm_key.begin(), lsm_key.end());
     Codec::decode(lsm_key_bytes, table_id);
     if (table_id != table_->table_id()) {
       LOG_TRACE("table id not match, table id: %ld", table_->table_id());
@@ -66,4 +67,5 @@ RC LsmRecordScanner::next(Record &record)
     return RC::RECORD_EOF;
   }
   return RC::SUCCESS;
-}
\ No newline at end of file
+}
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/lsm_record_scanner.h b/src/observer/storage/record/lsm_record_scanner.h
index 6407fae27..8987f44e6 100644
--- a/src/observer/storage/record/lsm_record_scanner.h
+++ b/src/observer/storage/record/lsm_record_scanner.h
@@ -17,6 +17,9 @@ See the Mulan PSL v2 for more details. */
 #include "storage/trx/trx.h"
 
 using namespace oceanbase;
+
+namespace oceanbase {
+
 class LsmRecordScanner : public RecordScanner
 {
 public:
@@ -47,4 +50,5 @@ class LsmRecordScanner : public RecordScanner
   ObLsmIterator *lsm_iter_ = nullptr;
   RowTuple       tuple_;
   Record         record_;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/record.h b/src/observer/storage/record/record.h
index 308355193..711c7524f 100644
--- a/src/observer/storage/record/record.h
+++ b/src/observer/storage/record/record.h
@@ -25,6 +25,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/field/field_meta.h"
 #include "storage/index/index_meta.h"
 
+namespace oceanbase {
+
 class Field;
 
 /**
@@ -266,3 +268,4 @@ class Record
   int    len_   = 0;      /// 如果不是record自己来管理内存，这个字段可能是无效的
   bool   owner_ = false;  /// 表示当前是否由record来管理内存
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/record_log.cpp b/src/observer/storage/record/record_log.cpp
index 3af38bd07..2a537eca3 100644
--- a/src/observer/storage/record/record_log.cpp
+++ b/src/observer/storage/record/record_log.cpp
@@ -29,6 +29,8 @@ using namespace common;
 
 // class RecordOperation
 
+namespace oceanbase {
+
 string RecordOperation::to_string() const
 {
   string ret = std::to_string(type_id()) + ":";
@@ -329,3 +331,4 @@ RC RecordLogReplayer::replay_update(DiskBufferPool &buffer_pool, const RecordLog
 
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/record_log.h b/src/observer/storage/record/record_log.h
index 5bf5663b6..c162c0af2 100644
--- a/src/observer/storage/record/record_log.h
+++ b/src/observer/storage/record/record_log.h
@@ -23,6 +23,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/clog/log_replayer.h"
 #include "sql/parser/parse_defs.h"
 
+namespace oceanbase {
+
 struct RID;
 class LogHandler;
 class Frame;
@@ -153,3 +155,4 @@ class RecordLogReplayer final : public LogReplayer
 private:
   BufferPoolManager &bpm_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/record_manager.cpp b/src/observer/storage/record/record_manager.cpp
index 87e5a6105..7be630f16 100644
--- a/src/observer/storage/record/record_manager.cpp
+++ b/src/observer/storage/record/record_manager.cpp
@@ -19,6 +19,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 static constexpr int PAGE_HEADER_SIZE = (sizeof(PageHeader));
 RecordPageHandler   *RecordPageHandler::create(StorageFormat format)
 {
@@ -799,3 +801,4 @@ RC ChunkFileScanner::next_chunk(Chunk &chunk)
   record_page_handler_->cleanup();
   return RC::RECORD_EOF;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/record_manager.h b/src/observer/storage/record/record_manager.h
index 876e29b28..f1a77c203 100644
--- a/src/observer/storage/record/record_manager.h
+++ b/src/observer/storage/record/record_manager.h
@@ -23,6 +23,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/lob_handler.h"
 #include "common/types.h"
 
+namespace oceanbase {
+
 class LogHandler;
 class ConditionFilter;
 class RecordPageHandler;
@@ -261,12 +263,12 @@ class RecordPageHandler
 protected:
   DiskBufferPool  *disk_buffer_pool_ = nullptr;  ///< 当前操作的buffer pool(文件)
   RecordLogHandler log_handler_;                 ///< 当前操作的日志处理器
-  Frame *frame_ = nullptr;  ///< 当前操作页面关联的frame(frame的更多概念可以参考buffer pool和frame)
-  ReadWriteMode   rw_mode_     = ReadWriteMode::READ_WRITE;  ///< 当前的操作是否都是只读的
-  PageHeader     *page_header_ = nullptr;                    ///< 当前页面上页面头
-  char           *bitmap_      = nullptr;  ///< 当前页面上record分配状态信息bitmap内存起始位置
-  StorageFormat   storage_format_;
-  LobFileHandler *lob_handler_ = nullptr;
+  Frame           *frame_       = nullptr;       ///< 当前操作页面关联的frame(frame的更多概念可以参考buffer pool和frame)
+  ReadWriteMode    rw_mode_     = ReadWriteMode::READ_WRITE;  ///< 当前的操作是否都是只读的
+  PageHeader      *page_header_ = nullptr;                    ///< 当前页面上页面头
+  char            *bitmap_      = nullptr;                    ///< 当前页面上record分配状态信息bitmap内存起始位置
+  StorageFormat    storage_format_;
+  LobFileHandler  *lob_handler_ = nullptr;
 
 protected:
   friend class RecordPageIterator;
@@ -365,7 +367,7 @@ class PaxRecordPageHandler : public RecordPageHandler
 class RecordFileHandler
 {
 public:
-  RecordFileHandler(StorageFormat storage_format) : storage_format_(storage_format){};
+  RecordFileHandler(StorageFormat storage_format) : storage_format_(storage_format) {};
   ~RecordFileHandler();
 
   /**
@@ -421,7 +423,7 @@ class RecordFileHandler
   DiskBufferPool        *disk_buffer_pool_ = nullptr;
   LogHandler            *log_handler_      = nullptr;  ///< 记录日志的处理器
   unordered_set<PageNum> free_pages_;                  ///< 没有填充满的页面集合
-  common::Mutex          lock_;  ///< 当编译时增加-DCONCURRENCY=ON 选项时，才会真正的支持并发
+  common::Mutex          lock_;                        ///< 当编译时增加-DCONCURRENCY=ON 选项时，才会真正的支持并发
   StorageFormat          storage_format_;
   TableMeta             *table_meta_;
   LobFileHandler        *lob_handler_ = nullptr;
@@ -456,8 +458,9 @@ class ChunkFileScanner
 
   DiskBufferPool *disk_buffer_pool_ = nullptr;  ///< 当前访问的文件
   LogHandler     *log_handler_      = nullptr;
-  ReadWriteMode   rw_mode_ = ReadWriteMode::READ_WRITE;  ///< 遍历出来的数据，是否可能对它做修改
+  ReadWriteMode   rw_mode_          = ReadWriteMode::READ_WRITE;  ///< 遍历出来的数据，是否可能对它做修改
 
   BufferPoolIterator bp_iterator_;                    ///< 遍历buffer pool的所有页面
   RecordPageHandler *record_page_handler_ = nullptr;  ///< 处理文件某页面的记录
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/record/record_scanner.h b/src/observer/storage/record/record_scanner.h
index 463b69724..c16855ca8 100644
--- a/src/observer/storage/record/record_scanner.h
+++ b/src/observer/storage/record/record_scanner.h
@@ -13,6 +13,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/record.h"
 #include "storage/common/condition_filter.h"
 
+namespace oceanbase {
+
 /**
  * @brief 遍历某个表中所有记录
  * @ingroup RecordManager
@@ -39,4 +41,5 @@ class RecordScanner
    * @param record 返回的下一条记录
    */
   virtual RC next(Record &record) = 0;
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/heap_table_engine.cpp b/src/observer/storage/table/heap_table_engine.cpp
index 6348c60e8..203d0736a 100644
--- a/src/observer/storage/table/heap_table_engine.cpp
+++ b/src/observer/storage/table/heap_table_engine.cpp
@@ -15,6 +15,7 @@ See the Mulan PSL v2 for more details. */
 #include "storage/common/meta_util.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
 
 HeapTableEngine::~HeapTableEngine()
 {
@@ -61,7 +62,7 @@ RC HeapTableEngine::insert_record(Record &record)
   return rc;
 }
 
-RC HeapTableEngine::insert_chunk(const Chunk& chunk)
+RC HeapTableEngine::insert_chunk(const Chunk &chunk)
 {
   RC rc = RC::SUCCESS;
   rc    = record_handler_->insert_chunk(chunk, table_meta_->record_size());
@@ -106,7 +107,7 @@ RC HeapTableEngine::delete_record(const Record &record)
 RC HeapTableEngine::get_record_scanner(RecordScanner *&scanner, Trx *trx, ReadWriteMode mode)
 {
   scanner = new HeapRecordScanner(table_, *data_buffer_pool_, trx, db_->log_handler(), mode, nullptr);
-  RC rc = scanner->open_scan();
+  RC rc   = scanner->open_scan();
   if (rc != RC::SUCCESS) {
     LOG_ERROR("failed to open scanner. rc=%s", strrc(rc));
   }
@@ -151,7 +152,7 @@ RC HeapTableEngine::create_index(Trx *trx, const FieldMeta *field_meta, const ch
 
   // 遍历当前的所有数据，插入这个索引
   RecordScanner *scanner = nullptr;
-  rc = get_record_scanner(scanner, trx, ReadWriteMode::READ_ONLY);
+  rc                     = get_record_scanner(scanner, trx, ReadWriteMode::READ_ONLY);
   if (rc != RC::SUCCESS) {
     LOG_WARN("failed to create scanner while creating index. table=%s, index=%s, rc=%s", 
              table_meta_->name(), index_name, strrc(rc));
@@ -341,3 +342,4 @@ RC HeapTableEngine::open()
   }
   return rc;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/heap_table_engine.h b/src/observer/storage/table/heap_table_engine.h
index 6726f86dc..d969be4d2 100644
--- a/src/observer/storage/table/heap_table_engine.h
+++ b/src/observer/storage/table/heap_table_engine.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/record_manager.h"
 #include "storage/db/db.h"
 
+namespace oceanbase {
+
 class Table;
 /**
  * @brief table engine
@@ -60,3 +62,4 @@ class HeapTableEngine : public TableEngine
   Db                *db_;
   Table             *table_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/lsm_table_engine.cpp b/src/observer/storage/table/lsm_table_engine.cpp
index c97d113a2..f5a19f752 100644
--- a/src/observer/storage/table/lsm_table_engine.cpp
+++ b/src/observer/storage/table/lsm_table_engine.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/common/codec.h"
 #include "storage/trx/lsm_mvcc_trx.h"
 
+namespace oceanbase {
+
 RC LsmTableEngine::insert_record(Record &record)
 {
   RC rc = RC::SUCCESS;
@@ -32,14 +34,13 @@ RC LsmTableEngine::insert_record(Record &record)
 RC LsmTableEngine::get_record_scanner(RecordScanner *&scanner, Trx *trx, ReadWriteMode mode)
 {
   scanner = new LsmRecordScanner(table_, db_->lsm(), trx);
-  RC rc = scanner->open_scan();
+  RC rc   = scanner->open_scan();
   if (rc != RC::SUCCESS) {
     LOG_ERROR("failed to open scanner. rc=%s", strrc(rc));
   }
   return rc;
 }
 
-RC LsmTableEngine::open()
-{
-  return RC::UNIMPLEMENTED;
-}
\ No newline at end of file
+RC LsmTableEngine::open() { return RC::UNIMPLEMENTED; }
+
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/lsm_table_engine.h b/src/observer/storage/table/lsm_table_engine.h
index be97cacd9..6acf84eb6 100644
--- a/src/observer/storage/table/lsm_table_engine.h
+++ b/src/observer/storage/table/lsm_table_engine.h
@@ -17,6 +17,8 @@ See the Mulan PSL v2 for more details. */
 #include "oblsm/include/ob_lsm.h"
 using namespace oceanbase;
 
+namespace oceanbase {
+
 /**
  * @brief lsm table engine
  */
@@ -56,3 +58,4 @@ class LsmTableEngine : public TableEngine
   ObLsm           *lsm_;
   atomic<uint64_t> inc_id_{0};
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/table.cpp b/src/observer/storage/table/table.cpp
index 14093fc06..4eb3df8c7 100644
--- a/src/observer/storage/table/table.cpp
+++ b/src/observer/storage/table/table.cpp
@@ -35,6 +35,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/table/heap_table_engine.h"
 #include "storage/table/lsm_table_engine.h"
 
+namespace oceanbase {
+
 Table::~Table()
 {
   if (lob_handler_ != nullptr) {
@@ -44,7 +46,8 @@ Table::~Table()
 }
 
 RC Table::create(Db *db, int32_t table_id, const char *path, const char *name, const char *base_dir,
-    span<const AttrInfoSqlNode> attributes, const vector<string> &primary_keys, StorageFormat storage_format, StorageEngine storage_engine)
+    span<const AttrInfoSqlNode> attributes, const vector<string> &primary_keys, StorageFormat storage_format,
+    StorageEngine storage_engine)
 {
   if (table_id < 0) {
     LOG_WARN("invalid table id. table_id=%d, table_name=%s", table_id, name);
@@ -80,7 +83,8 @@ RC Table::create(Db *db, int32_t table_id, const char *path, const char *name, c
 
   // 创建文件
   const vector<FieldMeta> *trx_fields = db->trx_kit().trx_fields();
-  if ((rc = table_meta_.init(table_id, name, trx_fields, attributes, primary_keys, storage_format, storage_engine)) != RC::SUCCESS) {
+  if ((rc = table_meta_.init(table_id, name, trx_fields, attributes, primary_keys, storage_format, storage_engine)) !=
+      RC::SUCCESS) {
     LOG_ERROR("Failed to init table meta. name:%s, ret:%d", name, rc);
     return rc;  // delete table file
   }
@@ -96,7 +100,7 @@ RC Table::create(Db *db, int32_t table_id, const char *path, const char *name, c
   table_meta_.serialize(fs);
   fs.close();
 
-  db_       = db;
+  db_ = db;
 
   string             data_file = table_data_file(base_dir, name);
   BufferPoolManager &bpm       = db->buffer_pool_manager();
@@ -142,7 +146,7 @@ RC Table::open(Db *db, const char *meta_file, const char *base_dir)
   }
   fs.close();
 
-  db_       = db;
+  db_ = db;
 
   // // 加载数据文件
   // RC rc = init_record_handler(base_dir);
@@ -155,7 +159,7 @@ RC Table::open(Db *db, const char *meta_file, const char *base_dir)
 
   if (table_meta_.storage_engine() == StorageEngine::HEAP) {
     engine_ = make_unique<HeapTableEngine>(&table_meta_, db_, this);
-  }  else if (table_meta_.storage_engine() == StorageEngine::LSM) {
+  } else if (table_meta_.storage_engine() == StorageEngine::LSM) {
     engine_ = make_unique<LsmTableEngine>(&table_meta_, db_, this);
   } else {
     rc = RC::UNSUPPORTED;
@@ -172,39 +176,24 @@ RC Table::open(Db *db, const char *meta_file, const char *base_dir)
   return rc;
 }
 
-RC Table::insert_record(Record &record)
-{
-  return engine_->insert_record(record);
-}
+RC Table::insert_record(Record &record) { return engine_->insert_record(record); }
 
-RC Table::insert_chunk(const Chunk& chunk)
-{
-  return engine_->insert_chunk(chunk);
-}
+RC Table::insert_chunk(const Chunk &chunk) { return engine_->insert_chunk(chunk); }
 
-RC Table::visit_record(const RID &rid, function<bool(Record &)> visitor)
-{
-  return engine_->visit_record(rid, visitor);
-}
+RC Table::visit_record(const RID &rid, function<bool(Record &)> visitor) { return engine_->visit_record(rid, visitor); }
 
-RC Table::insert_record_with_trx(Record &record, Trx *trx)
-{
-  return engine_->insert_record_with_trx(record, trx);
-}
+RC Table::insert_record_with_trx(Record &record, Trx *trx) { return engine_->insert_record_with_trx(record, trx); }
 RC Table::delete_record_with_trx(const Record &record, Trx *trx)
 {
   return engine_->delete_record_with_trx(record, trx);
 }
 
-RC Table::update_record_with_trx(const Record &old_record, const Record &new_record, Trx* trx)
+RC Table::update_record_with_trx(const Record &old_record, const Record &new_record, Trx *trx)
 {
   return engine_->update_record_with_trx(old_record, new_record, trx);
 }
 
-RC Table::get_record(const RID &rid, Record &record)
-{
-  return engine_->get_record(rid, record);
-}
+RC Table::get_record(const RID &rid, Record &record) { return engine_->get_record(rid, record); }
 
 const char *Table::name() const { return table_meta_.name(); }
 
@@ -227,7 +216,7 @@ RC Table::make_record(int value_num, const Value *values, Record &record)
 
   for (int i = 0; i < value_num && OB_SUCC(rc); i++) {
     const FieldMeta *field = table_meta_.field(i + normal_field_start_index);
-    const Value &    value = values[i];
+    const Value     &value = values[i];
     if (field->type() != value.attr_type()) {
       Value real_value;
       rc = Value::cast_to(value, field->type(), real_value);
@@ -279,21 +268,10 @@ RC Table::create_index(Trx *trx, const FieldMeta *field_meta, const char *index_
   return engine_->create_index(trx, field_meta, index_name);
 }
 
-RC Table::delete_record(const Record &record)
-{
-  return engine_->delete_record(record);
-}
+RC Table::delete_record(const Record &record) { return engine_->delete_record(record); }
 
-Index *Table::find_index(const char *index_name) const
-{
-  return engine_->find_index(index_name);
-}
-Index *Table::find_index_by_field(const char *field_name) const
-{
-  return engine_->find_index_by_field(field_name);
-}
+Index *Table::find_index(const char *index_name) const { return engine_->find_index(index_name); }
+Index *Table::find_index_by_field(const char *field_name) const { return engine_->find_index_by_field(field_name); }
 
-RC Table::sync()
-{
-  return engine_->sync();
-}
+RC Table::sync() { return engine_->sync(); }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/table.h b/src/observer/storage/table/table.h
index 0e5f89014..cdc8b0734 100644
--- a/src/observer/storage/table/table.h
+++ b/src/observer/storage/table/table.h
@@ -22,6 +22,8 @@ See the Mulan PSL v2 for more details. */
 #include "common/lang/span.h"
 #include "common/lang/functional.h"
 
+namespace oceanbase {
+
 struct RID;
 class Record;
 class DiskBufferPool;
@@ -140,3 +142,4 @@ class Table
   unique_ptr<TableEngine> engine_      = nullptr;
   LobFileHandler         *lob_handler_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/table_engine.h b/src/observer/storage/table/table_engine.h
index 110fbd046..51e621d8f 100644
--- a/src/observer/storage/table/table_engine.h
+++ b/src/observer/storage/table/table_engine.h
@@ -15,6 +15,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/table/table_meta.h"
 #include "storage/common/chunk.h"
 
+namespace oceanbase {
+
 struct RID;
 class Record;
 class DiskBufferPool;
@@ -60,3 +62,4 @@ class TableEngine
 protected:
   TableMeta *table_meta_ = nullptr;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/table_meta.cpp b/src/observer/storage/table/table_meta.cpp
index 144881188..64d876322 100644
--- a/src/observer/storage/table/table_meta.cpp
+++ b/src/observer/storage/table/table_meta.cpp
@@ -20,6 +20,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/trx/trx.h"
 #include "json/json.h"
 
+namespace oceanbase {
+
 static const Json::StaticString FIELD_TABLE_ID("table_id");
 static const Json::StaticString FIELD_TABLE_NAME("table_name");
 static const Json::StaticString FIELD_STORAGE_FORMAT("storage_format");
@@ -47,8 +49,8 @@ void TableMeta::swap(TableMeta &other) noexcept
 }
 
 RC TableMeta::init(int32_t table_id, const char *name, const vector<FieldMeta> *trx_fields,
-                   span<const AttrInfoSqlNode> attributes, const vector<string> &primary_keys, StorageFormat storage_format,
-                   StorageEngine storage_engine)
+    span<const AttrInfoSqlNode> attributes, const vector<string> &primary_keys, StorageFormat storage_format,
+    StorageEngine storage_engine)
 {
   if (common::is_blank(name)) {
     LOG_ERROR("Name cannot be empty");
@@ -71,7 +73,12 @@ RC TableMeta::init(int32_t table_id, const char *name, const vector<FieldMeta> *
     fields_.resize(attributes.size() + trx_fields->size());
     for (size_t i = 0; i < trx_fields->size(); i++) {
       const FieldMeta &field_meta = (*trx_fields)[i];
-      fields_[i] = FieldMeta(field_meta.name(), field_meta.type(), field_offset, field_meta.len(), false /*visible*/, field_meta.field_id());
+      fields_[i]                  = FieldMeta(field_meta.name(),
+          field_meta.type(),
+          field_offset,
+          field_meta.len(),
+          false /*visible*/,
+          field_meta.field_id());
       field_offset += field_meta.len();
     }
 
@@ -84,7 +91,7 @@ RC TableMeta::init(int32_t table_id, const char *name, const vector<FieldMeta> *
     const AttrInfoSqlNode &attr_info = attributes[i];
     // `i` is the col_id of fields[i]
     rc = fields_[i + trx_field_num].init(
-      attr_info.name.c_str(), attr_info.type, field_offset, attr_info.length, true /*visible*/, i);
+        attr_info.name.c_str(), attr_info.type, field_offset, attr_info.length, true /*visible*/, i);
     if (OB_FAIL(rc)) {
       LOG_ERROR("Failed to init field meta. table name=%s, field name: %s", name, attr_info.name.c_str());
       return rc;
@@ -94,10 +101,10 @@ RC TableMeta::init(int32_t table_id, const char *name, const vector<FieldMeta> *
   }
 
   primary_keys_ = primary_keys;
-  record_size_ = field_offset;
+  record_size_  = field_offset;
 
-  table_id_ = table_id;
-  name_     = name;
+  table_id_       = table_id;
+  name_           = name;
   storage_format_ = storage_format;
   storage_engine_ = storage_engine;
   LOG_INFO("Sussessfully initialized table meta. table id=%d, name=%s", table_id, name);
@@ -114,10 +121,7 @@ const char *TableMeta::name() const { return name_.c_str(); }
 
 const FieldMeta *TableMeta::trx_field() const { return &fields_[0]; }
 
-span<const FieldMeta> TableMeta::trx_fields() const
-{
-  return span<const FieldMeta>(fields_.data(), sys_field_num());
-}
+span<const FieldMeta> TableMeta::trx_fields() const { return span<const FieldMeta>(fields_.data(), sys_field_num()); }
 
 const FieldMeta *TableMeta::field(int index) const { return &fields_[index]; }
 const FieldMeta *TableMeta::field(const char *name) const
@@ -175,8 +179,8 @@ int TableMeta::record_size() const { return record_size_; }
 int TableMeta::serialize(ostream &ss) const
 {
   Json::Value table_value;
-  table_value[FIELD_TABLE_ID]   = table_id_;
-  table_value[FIELD_TABLE_NAME] = name_;
+  table_value[FIELD_TABLE_ID]       = table_id_;
+  table_value[FIELD_TABLE_NAME]     = name_;
   table_value[FIELD_STORAGE_FORMAT] = static_cast<int>(storage_format_);
   table_value[FIELD_STORAGE_ENGINE] = static_cast<int>(storage_engine_);
 
@@ -218,7 +222,7 @@ int TableMeta::deserialize(istream &is)
 {
   Json::Value             table_value;
   Json::CharReaderBuilder builder;
-  string             errors;
+  string                  errors;
 
   streampos old_pos = is.tellg();
   if (!Json::parseFromStream(builder, is, &table_value, &errors)) {
@@ -282,7 +286,7 @@ int TableMeta::deserialize(istream &is)
   auto comparator = [](const FieldMeta &f1, const FieldMeta &f2) { return f1.offset() < f2.offset(); };
   sort(fields.begin(), fields.end(), comparator);
 
-  table_id_ = table_id;
+  table_id_       = table_id;
   storage_format_ = static_cast<StorageFormat>(storage_format);
   storage_engine_ = static_cast<StorageEngine>(storage_engine);
   name_.swap(table_name);
@@ -291,7 +295,7 @@ int TableMeta::deserialize(istream &is)
 
   for (const FieldMeta &field_meta : fields_) {
     if (!field_meta.visible()) {
-      trx_fields_.push_back(field_meta); // 字段加上trx标识更好
+      trx_fields_.push_back(field_meta);  // 字段加上trx标识更好
     }
   }
 
@@ -301,7 +305,7 @@ int TableMeta::deserialize(istream &is)
       LOG_ERROR("Invalid table meta. indexes is not array, json value=%s", fields_value.toStyledString().c_str());
       return -1;
     }
-    const int              index_num = indexes_value.size();
+    const int         index_num = indexes_value.size();
     vector<IndexMeta> indexes(index_num);
     for (int i = 0; i < index_num; i++) {
       IndexMeta &index = indexes[i];
@@ -322,7 +326,7 @@ int TableMeta::deserialize(istream &is)
       LOG_ERROR("Invalid table meta. primary keys is not array, json value=%s", fields_value.toStyledString().c_str());
       return -1;
     }
-    const int              primary_key_num = primary_keys_value.size();
+    const int      primary_key_num = primary_keys_value.size();
     vector<string> primary_keys(primary_key_num);
     for (int i = 0; i < primary_key_num; i++) {
       const Json::Value &field_name_value = primary_keys_value[i];
@@ -360,3 +364,4 @@ void TableMeta::desc(ostream &os) const
   }
   os << ')' << endl;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/table/table_meta.h b/src/observer/storage/table/table_meta.h
index 12bf8f7b4..c6df68bf0 100644
--- a/src/observer/storage/table/table_meta.h
+++ b/src/observer/storage/table/table_meta.h
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/field/field_meta.h"
 #include "storage/index/index_meta.h"
 
+namespace oceanbase {
+
 /**
  * @brief 表元数据
  *
@@ -84,3 +86,4 @@ class TableMeta : public common::Serializable
 
   int record_size_ = 0;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/lsm_mvcc_trx.cpp b/src/observer/storage/trx/lsm_mvcc_trx.cpp
index 1f07ef6d6..0d1c7ddbc 100644
--- a/src/observer/storage/trx/lsm_mvcc_trx.cpp
+++ b/src/observer/storage/trx/lsm_mvcc_trx.cpp
@@ -10,6 +10,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/trx/lsm_mvcc_trx.h"
 
+namespace oceanbase {
+
 RC LsmMvccTrxKit::init() { return RC::SUCCESS; }
 
 const vector<FieldMeta> *LsmMvccTrxKit::trx_fields() const { return nullptr; }
@@ -27,15 +29,9 @@ LogReplayer *LsmMvccTrxKit::create_log_replayer(Db &, LogHandler &) { return new
 
 ////////////////////////////////////////////////////////////////////////////////
 
-RC LsmMvccTrx::insert_record(Table *table, Record &record)
-{
-   return table->insert_record_with_trx(record, this);
-}
+RC LsmMvccTrx::insert_record(Table *table, Record &record) { return table->insert_record_with_trx(record, this); }
 
-RC LsmMvccTrx::delete_record(Table *table, Record &record)
-{
-  return table->delete_record_with_trx(record, this);
-}
+RC LsmMvccTrx::delete_record(Table *table, Record &record) { return table->delete_record_with_trx(record, this); }
 
 RC LsmMvccTrx::update_record(Table *table, Record &old_record, Record &new_record)
 {
@@ -63,12 +59,10 @@ RC LsmMvccTrx::commit()
   return trx_->commit();
 }
 
-RC LsmMvccTrx::rollback()
-{
-  return trx_->rollback();
-}
+RC LsmMvccTrx::rollback() { return trx_->rollback(); }
 
 /**
  * 实际没有使用
  */
 RC LsmMvccTrx::redo(Db *, const LogEntry &) { return RC::SUCCESS; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/lsm_mvcc_trx.h b/src/observer/storage/trx/lsm_mvcc_trx.h
index 881eec08d..65bdf86f7 100644
--- a/src/observer/storage/trx/lsm_mvcc_trx.h
+++ b/src/observer/storage/trx/lsm_mvcc_trx.h
@@ -16,6 +16,9 @@ See the Mulan PSL v2 for more details. */
 #include "oblsm/include/ob_lsm_transaction.h"
 
 using namespace oceanbase;
+
+namespace oceanbase {
+
 /**
  * @brief lsm-tree 存储引擎对应的事务管理器
  */
@@ -77,4 +80,5 @@ class LsmMvccTrxLogReplayer : public LogReplayer
   virtual ~LsmMvccTrxLogReplayer() = default;
 
   RC replay(const LogEntry &) override { return RC::SUCCESS; }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/mvcc_trx.cpp b/src/observer/storage/trx/mvcc_trx.cpp
index e9ee76ab5..a4e560893 100644
--- a/src/observer/storage/trx/mvcc_trx.cpp
+++ b/src/observer/storage/trx/mvcc_trx.cpp
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/trx/mvcc_trx_log.h"
 #include "common/lang/algorithm.h"
 
+namespace oceanbase {
+
 MvccTrxKit::~MvccTrxKit()
 {
   vector<Trx *> tmp_trxes;
@@ -31,10 +33,11 @@ MvccTrxKit::~MvccTrxKit()
 RC MvccTrxKit::init()
 {
   // 事务使用一些特殊的字段，放到每行记录中，表示行记录的可见性。
-  fields_ = vector<FieldMeta>{
-      // field_id in trx fields is invisible.
-      FieldMeta("__trx_xid_begin", AttrType::INTS, 0 /*attr_offset*/, 4 /*attr_len*/, false /*visible*/, -1/*field_id*/),
-      FieldMeta("__trx_xid_end", AttrType::INTS, 0 /*attr_offset*/, 4 /*attr_len*/, false /*visible*/, -2/*field_id*/)};
+  fields_ = vector<FieldMeta>{// field_id in trx fields is invisible.
+      FieldMeta(
+          "__trx_xid_begin", AttrType::INTS, 0 /*attr_offset*/, 4 /*attr_len*/, false /*visible*/, -1 /*field_id*/),
+      FieldMeta(
+          "__trx_xid_end", AttrType::INTS, 0 /*attr_offset*/, 4 /*attr_len*/, false /*visible*/, -2 /*field_id*/)};
 
   LOG_INFO("init mvcc trx kit done.");
   return RC::SUCCESS;
@@ -99,11 +102,12 @@ LogReplayer *MvccTrxKit::create_log_replayer(Db &db, LogHandler &log_handler)
 
 ////////////////////////////////////////////////////////////////////////////////
 
-MvccTrx::MvccTrx(MvccTrxKit &kit, LogHandler &log_handler) : Trx(TrxKit::Type::MVCC), trx_kit_(kit), log_handler_(log_handler)
+MvccTrx::MvccTrx(MvccTrxKit &kit, LogHandler &log_handler)
+    : Trx(TrxKit::Type::MVCC), trx_kit_(kit), log_handler_(log_handler)
 {}
 
-MvccTrx::MvccTrx(MvccTrxKit &kit, LogHandler &log_handler, int32_t trx_id) 
-  : Trx(TrxKit::Type::MVCC), trx_kit_(kit), log_handler_(log_handler), trx_id_(trx_id)
+MvccTrx::MvccTrx(MvccTrxKit &kit, LogHandler &log_handler, int32_t trx_id)
+    : Trx(TrxKit::Type::MVCC), trx_kit_(kit), log_handler_(log_handler), trx_id_(trx_id)
 {
   started_    = true;
   recovering_ = true;
@@ -431,9 +435,9 @@ RC find_table(Db *db, const LogEntry &log_entry, Table *&table)
 
 RC MvccTrx::redo(Db *db, const LogEntry &log_entry)
 {
-  auto *trx_log_header = reinterpret_cast<const MvccTrxLogHeader *>(log_entry.data());
-  Table *table = nullptr;
-  RC     rc    = find_table(db, log_entry, table);
+  auto  *trx_log_header = reinterpret_cast<const MvccTrxLogHeader *>(log_entry.data());
+  Table *table          = nullptr;
+  RC     rc             = find_table(db, log_entry, table);
   if (OB_FAIL(rc)) {
     return rc;
   }
@@ -468,3 +472,4 @@ RC MvccTrx::redo(Db *db, const LogEntry &log_entry)
 
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/mvcc_trx.h b/src/observer/storage/trx/mvcc_trx.h
index 8db7c5ba1..04c2e2c62 100644
--- a/src/observer/storage/trx/mvcc_trx.h
+++ b/src/observer/storage/trx/mvcc_trx.h
@@ -18,6 +18,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/trx/trx.h"
 #include "storage/trx/mvcc_trx_log.h"
 
+namespace oceanbase {
+
 class CLogManager;
 class LogHandler;
 class MvccTrxLogHandler;
@@ -113,3 +115,4 @@ class MvccTrx : public Trx
   bool              recovering_ = false;
   OperationSet      operations_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/mvcc_trx_log.cpp b/src/observer/storage/trx/mvcc_trx_log.cpp
index abb4e7ba1..cc4edd0ad 100644
--- a/src/observer/storage/trx/mvcc_trx_log.cpp
+++ b/src/observer/storage/trx/mvcc_trx_log.cpp
@@ -23,6 +23,8 @@ See the Mulan PSL v2 for more details. */
 
 using namespace common;
 
+namespace oceanbase {
+
 string MvccTrxLogOperation::to_string() const
 {
   string ret = std::to_string(index()) + ":";
@@ -108,7 +110,7 @@ RC MvccTrxLogHandler::commit(int32_t trx_id, int32_t commit_trx_id)
   log_entry.commit_trx_id         = commit_trx_id;
 
   LSN lsn = 0;
-  RC rc = log_handler_.append(
+  RC  rc  = log_handler_.append(
       lsn, LogModule::Id::TRANSACTION, span<const char>(reinterpret_cast<const char *>(&log_entry), sizeof(log_entry)));
   if (OB_FAIL(rc)) {
     return rc;
@@ -134,7 +136,7 @@ RC MvccTrxLogHandler::rollback(int32_t trx_id)
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 MvccTrxLogReplayer::MvccTrxLogReplayer(Db &db, MvccTrxKit &trx_kit, LogHandler &log_handler)
-  : db_(db), trx_kit_(trx_kit), log_handler_(log_handler)
+    : db_(db), trx_kit_(trx_kit), log_handler_(log_handler)
 {}
 
 RC MvccTrxLogReplayer::replay(const LogEntry &entry)
@@ -150,9 +152,9 @@ RC MvccTrxLogReplayer::replay(const LogEntry &entry)
     return RC::LOG_ENTRY_INVALID;
   }
 
-  auto *header = reinterpret_cast<const MvccTrxLogHeader *>(entry.data());
-  MvccTrx *trx = nullptr;
-  auto trx_iter = trx_map_.find(header->trx_id);
+  auto    *header   = reinterpret_cast<const MvccTrxLogHeader *>(entry.data());
+  MvccTrx *trx      = nullptr;
+  auto     trx_iter = trx_map_.find(header->trx_id);
   if (trx_iter == trx_map_.end()) {
     trx = static_cast<MvccTrx *>(trx_kit_.create_trx(log_handler_, header->trx_id));
     // trx = new MvccTrx(trx_kit_, log_handler_, header->trx_id);
@@ -179,10 +181,11 @@ RC MvccTrxLogReplayer::on_done()
   /// 日志回放已经完成，需要把没有提交的事务，回滚掉
   for (auto &pair : trx_map_) {
     MvccTrx *trx = pair.second;
-    trx->rollback(); // 恢复时的rollback，可能遇到之前已经回滚一半的事务又再次调用回滚的情况
+    trx->rollback();  // 恢复时的rollback，可能遇到之前已经回滚一半的事务又再次调用回滚的情况
     delete pair.second;
   }
   trx_map_.clear();
 
   return RC::SUCCESS;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/mvcc_trx_log.h b/src/observer/storage/trx/mvcc_trx_log.h
index 0e670228e..4402bc6fb 100644
--- a/src/observer/storage/trx/mvcc_trx_log.h
+++ b/src/observer/storage/trx/mvcc_trx_log.h
@@ -21,6 +21,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/record.h"
 #include "storage/clog/log_replayer.h"
 
+namespace oceanbase {
+
 class LogHandler;
 class Table;
 class Db;
@@ -162,3 +164,4 @@ class MvccTrxLogReplayer final : public LogReplayer
   ///< 事务ID到事务的映射。在重做结束后，如果还有未提交的事务，需要回滚。
   unordered_map<int32_t, MvccTrx *> trx_map_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/trx.cpp b/src/observer/storage/trx/trx.cpp
index 040192755..40c45a310 100644
--- a/src/observer/storage/trx/trx.cpp
+++ b/src/observer/storage/trx/trx.cpp
@@ -23,7 +23,9 @@ See the Mulan PSL v2 for more details. */
 #include "storage/trx/trx.h"
 #include "storage/trx/vacuous_trx.h"
 
-TrxKit *TrxKit::create(const char *name, Db* db)
+namespace oceanbase {
+
+TrxKit *TrxKit::create(const char *name, Db *db)
 {
   TrxKit *trx_kit = nullptr;
   if (common::is_blank(name) || 0 == strcasecmp(name, "vacuous")) {
@@ -43,6 +45,7 @@ TrxKit *TrxKit::create(const char *name, Db* db)
     delete trx_kit;
     trx_kit = nullptr;
   }
-  
+
   return trx_kit;
 }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/trx.h b/src/observer/storage/trx/trx.h
index 5aa777d27..7c19cff2c 100644
--- a/src/observer/storage/trx/trx.h
+++ b/src/observer/storage/trx/trx.h
@@ -24,6 +24,8 @@ See the Mulan PSL v2 for more details. */
 #include "storage/record/record_manager.h"
 #include "storage/table/table.h"
 
+namespace oceanbase {
+
 /**
  * @defgroup Transaction
  * @brief 事务相关的内容
@@ -160,3 +162,4 @@ class Trx
 private:
   TrxKit::Type type_;
 };
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/vacuous_trx.cpp b/src/observer/storage/trx/vacuous_trx.cpp
index 737f243b7..fec3a5f01 100644
--- a/src/observer/storage/trx/vacuous_trx.cpp
+++ b/src/observer/storage/trx/vacuous_trx.cpp
@@ -14,6 +14,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/trx/vacuous_trx.h"
 
+namespace oceanbase {
+
 RC VacuousTrxKit::init() { return RC::SUCCESS; }
 
 const vector<FieldMeta> *VacuousTrxKit::trx_fields() const { return nullptr; }
@@ -43,3 +45,4 @@ RC VacuousTrx::commit() { return RC::SUCCESS; }
 RC VacuousTrx::rollback() { return RC::SUCCESS; }
 
 RC VacuousTrx::redo(Db *, const LogEntry &) { return RC::SUCCESS; }
+}  // namespace oceanbase
\ No newline at end of file
diff --git a/src/observer/storage/trx/vacuous_trx.h b/src/observer/storage/trx/vacuous_trx.h
index 92adde90f..c882e91e9 100644
--- a/src/observer/storage/trx/vacuous_trx.h
+++ b/src/observer/storage/trx/vacuous_trx.h
@@ -16,6 +16,8 @@ See the Mulan PSL v2 for more details. */
 
 #include "storage/trx/trx.h"
 
+namespace oceanbase {
+
 /**
  * @brief Vacuous(真空的)，顾名思义就是没有实现事务功能
  */
@@ -63,4 +65,5 @@ class VacuousTrxLogReplayer : public LogReplayer
   virtual ~VacuousTrxLogReplayer() = default;
 
   RC replay(const LogEntry &) override { return RC::SUCCESS; }
-};
\ No newline at end of file
+};
+}  // namespace oceanbase
\ No newline at end of file