MCP PostgreSQL Server

A Model Context Protocol server that provides PostgreSQL database operations. This server enables AI models to interact with PostgreSQL databases through a standardized interface.

Installation

Manual Installation

npm install mcp-postgres-server

Or run directly with:

npx mcp-postgres-server

Configuration

The server requires the following environment variables:

{
  "mcpServers": {
    "postgres": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "mcp-postgres-server"],
      "env": {
        "PG_HOST": "your_host",
        "PG_PORT": "5432",
        "PG_USER": "your_user",
        "PG_PASSWORD": "your_password",
        "PG_DATABASE": "your_database"
      }
    }
  }
}

Available Tools

1. connect_db

Establish connection to PostgreSQL database using provided credentials.

use_mcp_tool({
  server_name: "postgres",
  tool_name: "connect_db",
  arguments: {
    host: "localhost",
    port: 5432,
    user: "your_user",
    password: "your_password",
    database: "your_database"
  }
});

2. query

Execute SELECT queries with optional prepared statement parameters. Supports both PostgreSQL-style ($1, $2) and MySQL-style (?) parameter placeholders.

use_mcp_tool({
  server_name: "postgres",
  tool_name: "query",
  arguments: {
    sql: "SELECT * FROM users WHERE id = $1",
    params: [1]
  }
});

3. execute

Execute INSERT, UPDATE, or DELETE queries with optional prepared statement parameters. Supports both PostgreSQL-style ($1, $2) and MySQL-style (?) parameter placeholders.

use_mcp_tool({
  server_name: "postgres",
  tool_name: "execute",
  arguments: {
    sql: "INSERT INTO users (name, email) VALUES ($1, $2)",
    params: ["John Doe", "john@example.com"]
  }
});

4. list_schemas

List all schemas in the connected database.

use_mcp_tool({
  server_name: "postgres",
  tool_name: "list_schemas",
  arguments: {}
});

5. list_tables

List tables in the connected database. Accepts an optional schema parameter (defaults to 'public').

// List tables in the 'public' schema (default)
use_mcp_tool({
  server_name: "postgres",
  tool_name: "list_tables",
  arguments: {}
});

// List tables in a specific schema
use_mcp_tool({
  server_name: "postgres",
  tool_name: "list_tables",
  arguments: {
    schema: "my_schema"
  }
});

6. describe_table

Get the structure of a specific table. Accepts an optional schema parameter (defaults to 'public').

// Describe a table in the 'public' schema (default)
use_mcp_tool({
  server_name: "postgres",
  tool_name: "describe_table",
  arguments: {
    table: "users"
  }
});

// Describe a table in a specific schema
use_mcp_tool({
  server_name: "postgres",
  tool_name: "describe_table",
  arguments: {
    table: "users",
    schema: "my_schema"
  }
});

Features

Secure connection handling with automatic cleanup
Prepared statement support for query parameters
Support for both PostgreSQL-style ($1, $2) and MySQL-style (?) parameter placeholders
Comprehensive error handling and validation
TypeScript support
Automatic connection management
Supports PostgreSQL-specific syntax and features
Multi-schema support for database operations

Security

Uses prepared statements to prevent SQL injection
Supports secure password handling through environment variables
Validates queries before execution
Automatically closes connections when done

Error Handling

The server provides detailed error messages for common issues:

Connection failures
Invalid queries
Missing parameters
Database errors

License

MIT

Integrations