Mini SQL Interpreter for CSV Files

📌 Overview

This project implements a lightweight SQL-like interpreter for querying CSV files using Flex (Lexical Analysis) and Bison (Syntax Analysis). It demonstrates compiler construction principles applied to real-world data filtering without requiring a full database system.

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✨ Features

• SQL-like query syntax

SELECT column1, column2 FROM filename.csv WHERE column condition value;

• Supports:
  • Multiple column selection
  • WHERE clause with numeric and string conditions
  • Lightweight and fast (no DBMS needed)
  • Works with any CSV file

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🛠 Tools & Technologies

• Flex – Lexical Analyzer
• Bison – Parser Generator
• C Language
• GCC
• Linux

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📂 Project Structure

mini-sql-interpreter/
├── lexer.l # Token definitions (Flex)
├── parser.y # Grammar rules (Bison)
├── csv_utils.c # CSV processing logic
├── csv_utils.h # Function declarations
├── main.c # Entry point
├── Makefile # Build script
├── people.csv # Sample data
└── README.md # Documentation

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🚀 Getting Started - Linux

1. Install Flex Bison

sudo apt-get install flex bison

2. Clone the repository:

git clone https://github.com/Slightsmile/Mini-Sql-Interpreter.git
cd mini-sql-interpreter

3. Build the project:

make

4. Run the interpreter:

./mini_sql

5. Example Queries:

SELECT name, age FROM people.csv WHERE age > 30;
SELECT name, city FROM people.csv WHERE city = "Dhaka";

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📷 Example Output

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⚠️ Error Handling

• Invalid query → Error: syntax error
• Missing file → Cannot open CSV file

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📜 License

This project is open source and available under the MIT License. Feel free to use and modify it for personal use.

Developed as a part of the Compiler Desgin Lab Project at Daffodil International University.