MCP SQL Server

A Model Context Protocol (MCP) server that provides SQL Server database query capabilities.

Features

• SQL Server database support using tedious driver
• No native dependencies - pure JavaScript implementation
• Simple query tool for executing SQL statements
• Environment variable based configuration
• Support for encrypted and unencrypted connections

Installation

npm install
npm run build

Configuration

Configure the server using environment variables:

• DB_HOST: SQL Server host (default: localhost)
• DB_PORT: SQL Server port (default: 1433)
• DB_DATABASE (required): Database name
• DB_USER (required): Database user
• DB_PASSWORD: Database password
• DB_TRUST_SERVER_CERTIFICATE: Set to true to trust server certificate (default: false)
• DB_ENCRYPT: Set to false to disable encryption (default: true)

Usage

Basic Example

DB_HOST=localhost \
DB_PORT=1433 \
DB_DATABASE=mydb \
DB_USER=sa \
DB_PASSWORD=MyPassword123! \
npm start

With Trusted Certificate

DB_HOST=sqlserver.example.com \
DB_DATABASE=production \
DB_USER=appuser \
DB_PASSWORD=SecurePass \
DB_TRUST_SERVER_CERTIFICATE=true \
npm start

Without Encryption (for local development)

DB_HOST=localhost \
DB_DATABASE=testdb \
DB_USER=sa \
DB_PASSWORD=DevPassword \
DB_ENCRYPT=false \
npm start

MCP Integration

This server provides one tool:

• query: Execute SQL queries against the connected SQL Server database
  • Parameters:
    • sql (string): The SQL query to execute
  • Returns: JSON formatted query results

Example Queries

-- Select data
SELECT TOP 10 * FROM Users

-- Join tables
SELECT o.OrderID, c.CustomerName, o.OrderDate
FROM Orders o
INNER JOIN Customers c ON o.CustomerID = c.CustomerID

-- Aggregate data
SELECT COUNT(*) as TotalOrders, SUM(Amount) as TotalRevenue
FROM Orders
WHERE OrderDate >= '2024-01-01'

Development

# Install dependencies
npm install

# Run in development mode
DB_HOST=localhost \
DB_DATABASE=testdb \
DB_USER=sa \
DB_PASSWORD=TestPass123! \
npm run dev

# Build for production
npm run build

Troubleshooting

Connection Issues

1. Login failed: Ensure SQL Server authentication is enabled and credentials are correct
2. Certificate error: Set DB_TRUST_SERVER_CERTIFICATE=true for self-signed certificates
3. Encryption error: Set DB_ENCRYPT=false for older SQL Server versions or local development
4. Network error: Check firewall settings and ensure SQL Server is listening on the correct port

SQL Server Configuration

Ensure your SQL Server instance:

• Has SQL Server authentication enabled (not just Windows authentication)
• Is configured to accept TCP/IP connections
• Has the necessary firewall rules configured

License

MIT