graphjin

GraphJin - Connect AI to Your Database

Point GraphJin at any database and AI assistants can query it instantly. Auto-discovers your schema, understands relationships, compiles to optimized SQL. No configuration required.

Works with PostgreSQL, MySQL, MongoDB, SQLite, Oracle, MSSQL - and models from Claude/GPT-4 to local 7B models.

Try It Now

# With Claude Desktop - run the demo
graphjin mcp demo --path examples/webshop/config
graphjin mcp demo info  # Copy output to Claude Desktop config

# With your own database
graphjin mcp --path /path/to/config
graphjin mcp info  # Copy output to Claude Desktop config

Within minutes, ask Claude: "What products do we have?" or "Show me orders from last week"

How It Works

1. Connects to database - Reads your schema automatically
2. Discovers relationships - Foreign keys become navigable joins
3. Exposes MCP tools - Teach any LLM the query syntax
4. Compiles to SQL - Every request becomes a single optimized query

No resolvers. No ORM. No N+1 queries. Just point and query.

What AI Can Do

Simple queries with filters:

{ products(where: { price: { gt: 50 } }, limit: 10) { id name price } }

Nested relationships:

{
  orders(limit: 5) {
    id total
    customer { name email }
    items { quantity product { name category { name } } }
  }
}

Aggregations:

{ products { count_id sum_price avg_price } }

Mutations:

mutation {
  products(insert: { name: "New Product", price: 29.99 }) { id }
}

Spatial queries:

{
  stores(where: { location: { st_dwithin: { point: [-122.4, 37.7], distance: 1000 } } }) {
    name address
  }
}

Real-time Subscriptions

Get live updates when your data changes. GraphJin handles thousands of concurrent subscribers with a single database query - not one per subscriber.

subscription {
  orders(where: { user_id: { eq: $user_id } }) {
    id total status
    items { product { name } }
  }
}

Why it's efficient:

• Traditional approach: 1,000 subscribers = 1,000 database queries
• GraphJin: 1,000 subscribers = 1 optimized batch query
• Automatic change detection - updates only sent when data actually changes
• Built-in cursor pagination for feeds and infinite scroll

Works from Node.js, Go, or any WebSocket client.

MCP Tools

GraphJin exposes 15 tools that guide AI models to write valid queries. Key tools: list_tables and describe_table for schema discovery, get_query_syntax for learning the DSL, execute_graphql for running queries, and execute_saved_query for production-approved queries. Prompts like write_query and fix_query_error help models construct and debug queries.

Database Support

Also works with AWS Aurora/RDS, Google Cloud SQL, and YugabyteDB.

Production Security

Query allow-lists - In production, only saved queries can run. AI models call execute_saved_query with pre-approved queries. No arbitrary SQL injection possible.

Role-based access - Different roles see different data:

roles:
  user:
    tables:
      - name: orders
        query:
          filters: ["{ user_id: { eq: $user_id } }"]

JWT authentication - Supports Auth0, Firebase, JWKS endpoints.

Response caching - Redis with in-memory fallback. Automatic cache invalidation.

CLI Reference

# Run MCP server (stdio mode for Claude Desktop)
graphjin mcp --path /path/to/config

# Show Claude Desktop config JSON
graphjin mcp info

# Run with temporary database container
graphjin mcp demo --path examples/webshop/config

# Show demo mode config JSON
graphjin mcp demo info

# Keep data between restarts
graphjin mcp demo --persist

# Override database type
graphjin mcp demo --db mysql

# Set auth context
graphjin mcp --user-id admin --user-role admin

Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "my-database": {
      "command": "graphjin",
      "args": ["mcp", "--path", "/path/to/config"],
      "env": {
        "GRAPHJIN_USER_ID": "admin",
        "GRAPHJIN_USER_ROLE": "admin"
      }
    }
  }
}

Also a GraphQL API

GraphJin works as a traditional API too - use it from Node.js, Go, or as a standalone service.

Node.js

npm install graphjin

import graphjin from "graphjin";
import pg from "pg";

const db = new pg.Client({ host: "localhost", database: "myapp" });
await db.connect();

const gj = await graphjin("./config", "dev.yml", db);
const result = await gj.query("{ users(id: $id) { id email } }", { id: 1 });
console.log(result.data());

Go

go get github.com/dosco/graphjin/core/v3

db, _ := sql.Open("pgx", "postgres://localhost/myapp")
gj, _ := core.NewGraphJin(nil, db)
res, _ := gj.GraphQL(ctx, `{ users { id email } }`, nil, nil)

Standalone Service

brew install dosco/graphjin/graphjin  # Mac
graphjin new myapp && cd myapp
graphjin serve

Built-in web UI at http://localhost:8080 for query development.

Documentation

• Quick Start
• Full Documentation
• Feature Reference
• Go Examples

Get in Touch

Twitter @dosco | Discord

License

Apache Public License 2.0