Add EXPLAIN AST support for ALTER, OPTIMIZE, and TRUNCATE queries

internal/explain/explain.go

@@ -137,6 +137,12 @@ func Node(sb *strings.Builder, node interface{}, depth int) {
 		explainDetachQuery(sb, n, indent)
 	case *ast.AttachQuery:
 		explainAttachQuery(sb, n, indent)
+	case *ast.AlterQuery:
+		explainAlterQuery(sb, n, indent, depth)
+	case *ast.OptimizeQuery:
+		explainOptimizeQuery(sb, n, indent)
+	case *ast.TruncateQuery:
+		explainTruncateQuery(sb, n, indent)
 
 	// Types
 	case *ast.DataType:

internal/explain/statements.go

@@ -550,3 +550,215 @@ func explainDetachQuery(sb *strings.Builder, n *ast.DetachQuery, indent string)
 func explainAttachQuery(sb *strings.Builder, n *ast.AttachQuery, indent string) {
 	fmt.Fprintf(sb, "%sAttachQuery\n", indent)
 }
+
+func explainAlterQuery(sb *strings.Builder, n *ast.AlterQuery, indent string, depth int) {
+	if n == nil {
+		fmt.Fprintf(sb, "%s*ast.AlterQuery\n", indent)
+		return
+	}
+
+	name := n.Table
+	if n.Database != "" {
+		name = n.Database + "." + n.Table
+	}
+
+	children := 2
+	fmt.Fprintf(sb, "%sAlterQuery  %s (children %d)\n", indent, name, children)
+	fmt.Fprintf(sb, "%s ExpressionList (children %d)\n", indent, len(n.Commands))
+	for _, cmd := range n.Commands {
+		explainAlterCommand(sb, cmd, indent+"  ", depth+2)
+	}
+	fmt.Fprintf(sb, "%s Identifier %s\n", indent, name)
+}
+
+func explainAlterCommand(sb *strings.Builder, cmd *ast.AlterCommand, indent string, depth int) {
+	children := countAlterCommandChildren(cmd)
+	fmt.Fprintf(sb, "%sAlterCommand %s (children %d)\n", indent, cmd.Type, children)
+
+	switch cmd.Type {
+	case ast.AlterAddColumn:
+		if cmd.Column != nil {
+			Column(sb, cmd.Column, depth+1)
+		}
+		if cmd.AfterColumn != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.AfterColumn)
+		}
+	case ast.AlterModifyColumn:
+		if cmd.Column != nil {
+			Column(sb, cmd.Column, depth+1)
+		}
+		if cmd.AfterColumn != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.AfterColumn)
+		}
+	case ast.AlterDropColumn:
+		if cmd.ColumnName != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.ColumnName)
+		}
+	case ast.AlterRenameColumn:
+		if cmd.ColumnName != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.ColumnName)
+		}
+		if cmd.NewName != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.NewName)
+		}
+	case ast.AlterClearColumn:
+		if cmd.ColumnName != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.ColumnName)
+		}
+		if cmd.Partition != nil {
+			Node(sb, cmd.Partition, depth+1)
+		}
+	case ast.AlterCommentColumn:
+		if cmd.ColumnName != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.ColumnName)
+		}
+	case ast.AlterAddIndex, ast.AlterDropIndex, ast.AlterClearIndex, ast.AlterMaterializeIndex:
+		if cmd.Index != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.Index)
+		}
+	case ast.AlterAddConstraint:
+		if cmd.Constraint != nil {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.Constraint.Name)
+		}
+	case ast.AlterDropConstraint:
+		if cmd.ConstraintName != "" {
+			fmt.Fprintf(sb, "%s Identifier %s\n", indent, cmd.ConstraintName)
+		}
+	case ast.AlterModifyTTL:
+		if cmd.TTL != nil && cmd.TTL.Expression != nil {
+			Node(sb, cmd.TTL.Expression, depth+1)
+		}
+	case ast.AlterModifySetting:
+		fmt.Fprintf(sb, "%s Set\n", indent)
+	case ast.AlterDropPartition, ast.AlterDetachPartition, ast.AlterAttachPartition,
+		ast.AlterReplacePartition, ast.AlterFreezePartition:
+		if cmd.Partition != nil {
+			Node(sb, cmd.Partition, depth+1)
+		}
+	case ast.AlterFreeze:
+		// No children
+	case ast.AlterDeleteWhere:
+		if cmd.Where != nil {
+			Node(sb, cmd.Where, depth+1)
+		}
+	case ast.AlterUpdate:
+		if len(cmd.Assignments) > 0 {
+			fmt.Fprintf(sb, "%s ExpressionList (children %d)\n", indent, len(cmd.Assignments))
+			for _, assign := range cmd.Assignments {
+				fmt.Fprintf(sb, "%s  Function equals (children 1)\n", indent)
+				fmt.Fprintf(sb, "%s   ExpressionList (children 2)\n", indent)
+				fmt.Fprintf(sb, "%s    Identifier %s\n", indent, assign.Column)
+				Node(sb, assign.Value, depth+4)
+			}
+		}
+		if cmd.Where != nil {
+			Node(sb, cmd.Where, depth+1)
+		}
+	default:
+		if cmd.Partition != nil {
+			Node(sb, cmd.Partition, depth+1)
+		}
+	}
+}
+
+func countAlterCommandChildren(cmd *ast.AlterCommand) int {
+	children := 0
+	switch cmd.Type {
+	case ast.AlterAddColumn, ast.AlterModifyColumn:
+		if cmd.Column != nil {
+			children++
+		}
+		if cmd.AfterColumn != "" {
+			children++
+		}
+	case ast.AlterDropColumn, ast.AlterCommentColumn:
+		if cmd.ColumnName != "" {
+			children++
+		}
+	case ast.AlterRenameColumn:
+		if cmd.ColumnName != "" {
+			children++
+		}
+		if cmd.NewName != "" {
+			children++
+		}
+	case ast.AlterClearColumn:
+		if cmd.ColumnName != "" {
+			children++
+		}
+		if cmd.Partition != nil {
+			children++
+		}
+	case ast.AlterAddIndex, ast.AlterDropIndex, ast.AlterClearIndex, ast.AlterMaterializeIndex:
+		if cmd.Index != "" {
+			children++
+		}
+	case ast.AlterAddConstraint:
+		if cmd.Constraint != nil {
+			children++
+		}
+	case ast.AlterDropConstraint:
+		if cmd.ConstraintName != "" {
+			children++
+		}
+	case ast.AlterModifyTTL:
+		if cmd.TTL != nil && cmd.TTL.Expression != nil {
+			children++
+		}
+	case ast.AlterModifySetting:
+		children = 1
+	case ast.AlterDropPartition, ast.AlterDetachPartition, ast.AlterAttachPartition,
+		ast.AlterReplacePartition, ast.AlterFreezePartition:
+		if cmd.Partition != nil {
+			children++
+		}
+	case ast.AlterFreeze:
+		// No children
+	case ast.AlterDeleteWhere:
+		if cmd.Where != nil {
+			children++
+		}
+	case ast.AlterUpdate:
+		if len(cmd.Assignments) > 0 {
+			children++
+		}
+		if cmd.Where != nil {
+			children++
+		}
+	default:
+		if cmd.Partition != nil {
+			children++
+		}
+	}
+	return children
+}
+
+func explainOptimizeQuery(sb *strings.Builder, n *ast.OptimizeQuery, indent string) {
+	if n == nil {
+		fmt.Fprintf(sb, "%s*ast.OptimizeQuery\n", indent)
+		return
+	}
+
+	name := n.Table
+	if n.Final {
+		name += "_final"
+	}
+
+	fmt.Fprintf(sb, "%sOptimizeQuery  %s (children %d)\n", indent, name, 1)
+	fmt.Fprintf(sb, "%s Identifier %s\n", indent, n.Table)
+}
+
+func explainTruncateQuery(sb *strings.Builder, n *ast.TruncateQuery, indent string) {
+	if n == nil {
+		fmt.Fprintf(sb, "%s*ast.TruncateQuery\n", indent)
+		return
+	}
+
+	name := n.Table
+	if n.Database != "" {
+		name = n.Database + "." + n.Table
+	}
+
+	fmt.Fprintf(sb, "%sTruncateQuery  %s (children %d)\n", indent, name, 1)
+	fmt.Fprintf(sb, "%s Identifier %s\n", indent, name)
+}

parser/testdata/00030_alter_table/metadata.json

@@ -1,21 +1,11 @@
 {
   "explain_todo": {
-    "stmt10": true,
-    "stmt12": true,
-    "stmt13": true,
     "stmt14": true,
     "stmt15": true,
     "stmt16": true,
-    "stmt17": true,
-    "stmt18": true,
     "stmt19": true,
     "stmt20": true,
-    "stmt21": true,
     "stmt22": true,
-    "stmt5": true,
-    "stmt6": true,
-    "stmt7": true,
-    "stmt8": true,
     "stmt9": true
   }
 }

parser/testdata/00041_aggregating_materialized_view/metadata.json

@@ -1,15 +1,5 @@
 {
   "explain_todo": {
-    "stmt10": true,
-    "stmt11": true,
-    "stmt12": true,
-    "stmt13": true,
-    "stmt14": true,
-    "stmt15": true,
-    "stmt16": true,
-    "stmt17": true,
-    "stmt18": true,
-    "stmt19": true,
     "stmt5": true
   }
 }

parser/testdata/00043_summing_empty_part/metadata.json

@@ -1 +1 @@
-{"explain_todo":{"stmt11":true,"stmt6":true}}
+{}

parser/testdata/00048_a_stored_aggregates_merge/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt10": true
-  }
-}
+{}

parser/testdata/00048_b_stored_aggregates_merge/metadata.json

@@ -1,5 +1 @@
-{
-  "explain_todo": {
-    "stmt10": true
-  }
-}
+{}

parser/testdata/00061_merge_tree_alter/metadata.json

@@ -1,24 +1,17 @@
 {
   "explain_todo": {
     "stmt11": true,
-    "stmt13": true,
     "stmt16": true,
-    "stmt18": true,
     "stmt21": true,
-    "stmt23": true,
     "stmt25": true,
-    "stmt27": true,
     "stmt29": true,
-    "stmt31": true,
     "stmt33": true,
     "stmt35": true,
     "stmt37": true,
     "stmt39": true,
     "stmt41": true,
     "stmt43": true,
-    "stmt45": true,
     "stmt47": true,
-    "stmt6": true,
-    "stmt8": true
+    "stmt6": true
   }
 }

parser/testdata/00061_storage_buffer/metadata.json

@@ -1,6 +1,5 @@
 {
   "explain_todo": {
-    "stmt3": true,
-    "stmt8": true
+    "stmt3": true
   }
 }

parser/testdata/00062_replicated_merge_tree_alter_zookeeper_long/metadata.json

@@ -1,22 +1,16 @@
 {
   "explain_todo": {
     "stmt11": true,
-    "stmt13": true,
     "stmt16": true,
     "stmt18": true,
-    "stmt20": true,
     "stmt23": true,
     "stmt25": true,
-    "stmt27": true,
     "stmt30": true,
     "stmt32": true,
-    "stmt34": true,
     "stmt37": true,
     "stmt39": true,
-    "stmt41": true,
     "stmt43": true,
     "stmt45": true,
-    "stmt47": true,
     "stmt49": true,
     "stmt51": true,
     "stmt53": true,
@@ -28,10 +22,8 @@
     "stmt65": true,
     "stmt67": true,
     "stmt69": true,
-    "stmt71": true,
     "stmt73": true,
     "stmt75": true,
-    "stmt77": true,
     "stmt79": true,
     "stmt81": true,
     "stmt9": true

parser/testdata/00071_merge_tree_optimize_aio/metadata.json

@@ -1,7 +1,6 @@
 {
   "explain_todo": {
     "stmt6": true,
-    "stmt7": true,
-    "stmt9": true
+    "stmt7": true
   }
 }

parser/testdata/00079_defaulted_columns/metadata.json

@@ -1,9 +1 @@
-{
-  "explain_todo": {
-    "stmt16": true,
-    "stmt22": true,
-    "stmt25": true,
-    "stmt28": true,
-    "stmt30": true
-  }
-}
+{}

parser/testdata/00084_summing_merge_tree/metadata.json

@@ -1 +1,5 @@
-{"explain_todo":{"stmt16":true,"stmt17":true,"stmt18":true,"stmt25":true,"stmt7":true,"stmt8":true,"stmt9":true}}
+{
+  "explain_todo": {
+    "stmt25": true
+  }
+}

parser/testdata/00121_drop_column_zookeeper/metadata.json

@@ -1,7 +1 @@
-{
-  "explain_todo": {
-    "stmt10": true,
-    "stmt13": true,
-    "stmt5": true
-  }
-}
+{}

parser/testdata/00140_prewhere_column_order/metadata.json

@@ -1 +1 @@
-{"explain_todo":{"stmt5":true}}
+{}

parser/testdata/00146_summing_merge_tree_nested_map/metadata.json

@@ -1,7 +1 @@
-{
-  "explain_todo": {
-    "stmt12": true,
-    "stmt19": true,
-    "stmt6": true
-  }
-}
+{}