How to Get Your Supabase Database URL and Run SQL Queries with Edge Functions

Supabase makes it easy to use a powerful PostgreSQL database in your projects. However, for security and best practices, Supabase does not provide a direct way to run arbitrary SQL queries from the dashboard or client-side code.
You should always run SQL queries from your backend or serverless (edge) functions.

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1. How to Get Your Supabase Database URL

To connect to your Supabase database, you need the connection string (URL). Here’s how to find it:

Step 1: Open Your Project and Click “Connect”

Go to your Supabase project dashboard.
Click the Connect button in the top right corner:

Click the “Connect” button to open the connection options.

Step 2: Copy the Database Connection String

A modal will appear with several connection options:

• Direct connection
• Transaction pooler (recommended for serverless/edge functions)
• Session pooler

For most backend and edge use cases, copy the Transaction pooler connection string:

Copy the connection string for your preferred pooler type. For serverless and edge functions, use the Transaction pooler.

Tip:

• Use the Transaction pooler for stateless, serverless, or edge environments.
• Use the Direct connection only for long-lived, persistent connections (e.g., VMs or containers).
• The Session pooler is for IPv4-only networks.

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2. How to Run SQL Queries Using the Database URL

Using Node.js (pg npm package)

Install the pg package:

npm install pg

Example code to run a SQL query:

const { Pool } = require('pg')

// Use your Transaction pooler connection string from Supabase
const pool = new Pool({
  connectionString: 'postgresql://postgres:[YOUR-PASSWORD]@aws-0-ap-southeast-1.pooler.supabase.com:5432/postgres?sslmode=require'
})

async function runQuery() {
  const client = await pool.connect()
  try {
    const res = await client.query('SELECT NOW()')
    console.log(res.rows)
  } finally {
    client.release()
  }
}

runQuery().catch(console.error)

Using Supabase Edge Functions (Deno)

You can use the connection string in your Edge Function with a Deno Postgres client:

import { serve } from 'https://deno.land/std@0.168.0/http/server.ts'
import { Pool } from 'https://deno.land/x/postgres@v0.17.0/mod.ts'

const pool = new Pool({
  hostname: Deno.env.get('DB_HOST'),
  database: Deno.env.get('DB_NAME'),
  user: Deno.env.get('DB_USER'),
  password: Deno.env.get('DB_PASSWORD'),
  port: 5432,
  tls: { enabled: true },
  max: 10,
})

serve(async (req) => {
  const client = await pool.connect()
  try {
    const result = await client.queryObject('SELECT NOW()')
    return new Response(JSON.stringify(result.rows), { headers: { 'Content-Type': 'application/json' } })
  } finally {
    client.release()
  }
})

Set your environment variables (DB_HOST, DB_NAME, etc.) using the values from your Supabase connection string.

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Important Security Note

• Never expose your database connection string in client-side code.
• Always run SQL queries from your backend or edge/serverless functions.
• Supabase recommends using their client libraries for most operations, but for custom SQL, always use a secure backend.

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Summary

• Get your database URL from the Supabase dashboard via the Connect button.
• Use the Transaction pooler connection string for most backend/edge/serverless use cases.
• Run SQL queries using the pg npm package (Node.js) or a Deno Postgres client (Edge Functions).
• Never run SQL queries directly from the client or expose your credentials.

Happy coding!