Skip to content

README.md

Latest commit

 

History

History
74 lines (57 loc) · 2.81 KB

README.md

File metadata and controls

74 lines (57 loc) · 2.81 KB
Raw

Mini SQL RDB

A fully custom mini relational database management system built from scratch in C++ and Qt6. It features a complete SQL frontend, a robust storage engine, a query executor, and a polished dark-themed GUI (along with a CLI mode).

Zero external database dependencies. No flex/bison. No SQLite under the hood.

Features

  • Storage Engine: 4KB slotted pages, LRU buffer pool manager, heap file organization, and B+Tree indexing for primary keys.
  • SQL Parser: Hand-written lexer and recursive descent parser supporting a practical subset of SQL (DDL and DML).
  • Query Engine: Volcano-style query execution pipeline with expression evaluation, query planning (index vs. full scan), joins, and aggregates.
  • Dual Interface:
    • IDE-like GUI: Features a SQL query editor with syntax highlighting, a schema explorer tree, and a data results table view.
    • Interactive CLI: A command-line REPL for executing queries and managing the database via meta-commands.
  • Data Types: INT, FLOAT, VARCHAR, BOOL, DATE.
  • Aesthetics: Modern Catppuccin Mocha-inspired dark theme for the Qt UI.

Project Structure

The project follows a clean architectural layout:

src/
├── core/       # Foundational types (DataType, Value, Row), error hierarchy, and the Database façade
├── storage/    # Disk I/O (Pages, Pager, Records, Tables, Catalog, BTree)
├── sql/        # SQL Tokenizer, Lexer, AST nodes, Parser, and QueryResult
├── engine/     # Expression Evaluator, Planner, and Executor
├── ui/         # Main Window, Query Editor, Results Table, Schema Explorer, Status Bar
└── theme/      # Dark theme definitions and SQL Syntax Highlighter

Build Instructions

This project uses CMake and requires Qt 6.

mkdir build
cd build
cmake ..
cmake --build . --config Release

Usage

GUI Mode

Simply run the executable without arguments to launch the IDE-like interface:

./MiniSQLRDB

Or provide a database file path to open it automatically:

./MiniSQLRDB my_database.minidb

CLI Mode

Pass the --cli flag to start the interactive command-line interface:

./MiniSQLRDB --cli my_database.minidb

Inside the CLI, you can use .help to see available meta-commands (like .tables, .open, .create) or type raw SQL terminated by a semicolon.

Supported SQL

  • DDL: CREATE TABLE, DROP TABLE, ALTER TABLE ADD COLUMN
  • DML: INSERT INTO, SELECT, UPDATE, DELETE
  • Clauses: WHERE, ORDER BY, LIMIT, GROUP BY, HAVING
  • Joins: INNER JOIN, LEFT JOIN
  • Aggregates: COUNT(), SUM(), AVG(), MIN(), MAX()
  • Operators: =, !=, <, >, <=, >=, AND, OR, NOT, LIKE, IS NULL, IS NOT NULL, BETWEEN, IN
  • Utility: SHOW TABLES, DESCRIBE <table>

License

MIT