Connecting Claude to PostgreSQL: A Quick Guide

I recently set up Claude to directly query my PostgreSQL database, enabling powerful natural language interactions with my data. Here's how you can do it too.

Key Capabilities

With Claude connected to PostgreSQL, you can:

• Ask questions about your data in natural language
• Have Claude translate your requests into SQL automatically
• Get immediate answers without writing queries yourself
• Explore your database through conversational interactions

For example, simply asking "How many entries are in the contact table?" produces accurate results instantly.

Setup Instructions

1. Configure the MCP Server

The Model Context Protocol (MCP) server for PostgreSQL doesn't require separate installation. Claude will use the NPX command specified in your configuration to access your database:

npx -y @modelcontextprotocol/server-postgres

You can find more details about this server implementation in the official repository on GitHub.

2. Ensure Compatible Node Version

Make sure you're using a modern Node.js version. If you're using NVM, you can switch to a recent version with:

nvm use stable

3. Configure Claude

Create or edit the Claude configuration file at:
~/Library/Application Support/Claude/claude_desktop_config.json

Use this format:

{
  "mcpServers": {
    "postgres": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-postgres",
        "postgresql://username@localhost:5432/database_name"
      ]
    }
  }
}

Remember to replace username, 5432, and database_name with your actual PostgreSQL username, port number, and database name. If your database requires a password, the format would be postgresql://username:password@localhost:5432/database_name. You can easily copy your connection string from database tools like Postico, which display this information in their connection settings.

Next Steps

With this foundation in place, you can explore more advanced use cases like complex data analysis, report generation, and interactive visualizations based on your PostgreSQL data.

The combination of natural language processing with direct database access significantly streamlines data exploration and analysis workflows.