MCP MySQL Server

A clean, simple, and well-organized Model Context Protocol (MCP) server for MySQL database interactions with Claude Desktop.

Features

• 🔍 Query Execution: Run SQL queries with proper validation and security
• 🗂️ Multi-Database Support: Switch between multiple databases easily
• 🔒 Security First: Read-only by default, configurable write permissions
• 📊 Schema Discovery: Automatic database and table schema information
• ⚡ Connection Pooling: Efficient database connection management
• 🛡️ Query Validation: Built-in SQL injection protection
• 📝 Comprehensive Logging: Optional detailed logging for debugging

Quick Start

1. Clone and Install

git clone <your-repo-url>
cd mcp-mysql-server
npm install

2. Configure Environment

cp .env.example .env
# Edit .env with your MySQL credentials

3. Build

npm run build

4. Configure Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "mysql-server": {
      "command": "node",
      "args": ["/full/path/to/mcp-mysql-server/dist/index.js"],
      "env": {
        "MYSQL_HOST": "localhost",
        "MYSQL_PORT": "3306", 
        "MYSQL_USER": "root",
        "MYSQL_PASSWORD": "your_password",
        "MYSQL_DATABASE": "your_database",
        "ENABLE_LOGGING": "true"
      }
    }
  }
}

Configuration Options

Basic Connection

• MYSQL_HOST: Database host (default: localhost)
• MYSQL_PORT: Database port (default: 3306)
• MYSQL_USER: Database username (default: root)
• MYSQL_PASSWORD: Database password
• MYSQL_DATABASE: Target database (leave empty for multi-DB mode)
• MYSQL_SOCKET_PATH: Unix socket path (optional, overrides host/port)

Security & Permissions

• ALLOW_WRITE: Enable all write operations (default: false)
• ALLOW_INSERT: Enable INSERT statements (default: false)
• ALLOW_UPDATE: Enable UPDATE statements (default: false)
• ALLOW_DELETE: Enable DELETE statements (default: false)
• ALLOW_DDL: Enable DDL operations CREATE/ALTER/DROP (default: false)

Performance Settings

• POOL_SIZE: Connection pool size (default: 10)
• QUERY_TIMEOUT: Query timeout in milliseconds (default: 30000)

Logging

• ENABLE_LOGGING: Enable detailed logging (default: false)

Multi-Database Mode

Leave MYSQL_DATABASE empty to enable multi-database mode. This allows querying any database the MySQL user has access to.

Example queries in multi-DB mode:

-- Use qualified table names
SELECT * FROM database_name.table_name;

-- Switch databases
USE database_name;
SELECT * FROM table_name;

Security Best Practices

1. Use Read-Only by Default: Only enable write operations when necessary
2. Create Dedicated MySQL User: Don't use root account
3. Limit Database Access: Grant permissions only to required databases
4. Backup Before Writes: Always backup data before enabling write operations
5. Monitor Query Logs: Enable logging to track database activities

Project Structure

src/
├── config/         # Configuration management
├── database/       # Database connection and management  
├── handlers/       # MCP request handlers
├── types/          # TypeScript type definitions
└── utils/          # Utility functions (logger, validator)

Development

# Development mode with auto-reload
npm run dev

# Watch mode for building
npm run watch

# Run tests
npm test

# Lint code
npm run lint