How do I get my PostgreSQL connection string?

In your database provider's dashboard, click Connect to retrieve your connection string. It typically looks like: postgresql://user:password@host:5432/dbname.

Which connection method should I use?

Select the Transaction pooler option. This ensures compatibility with stateless applications and allows dbdiagramr to detect connections properly.

What if I forgot my database password?

Regenerate your password in the Shared pooler section of your database provider's dashboard and copy-paste the new credentials into your connection string.

Supabase Connection String: IPv6, ENOTFOUND, and the Transaction Pooler Fix

The short version

Supabase uses IPv6 by default. Most local dev environments and many hosting providers don't support IPv6, so DNS resolution fails with ENOTFOUND or hangs with ETIMEDOUT. The fix: use the transaction pooler connection string (port 6543) instead of the direct connection (port 5432).

The error

Error: getaddrinfo ENOTFOUND db.xxxxxxxxx.supabase.co

This means DNS can't resolve the hostname to an IPv6 address. The second form (ETIMEDOUT) means DNS resolved but the connection timed out because your network doesn't route IPv6.

The three connection strings

Direct connection (port 5432)

Full Postgres protocol support. Supports prepared statements, SET commands, LISTEN/NOTIFY. Uses IPv6 -- may fail locally.

Transaction pooler (port 6543)

Routes through Supabase's PgBouncer. IPv4-compatible -- works everywhere. Does NOT support prepared statements or SET commands. Best for most web apps.

Session pooler (port 6543 + session_mode)

Same as transaction pooler but preserves session state. Supports SET but not prepared statements. Use if you need SET search_path.

Which one to use

Use case	Connection string
Local dev (Node.js, Python)	Transaction pooler (6543)
Vercel / Railway / Render	Transaction pooler (6543)
Cloudflare Workers	Transaction pooler (6543)
Prisma ORM	Transaction pooler (6543) + `?pgbouncer=true`
pg_dump / pg_restore	Direct connection (5432)
Migrations (Prisma, Knex)	Direct connection (5432)

The Prisma gotcha

Prisma uses prepared statements by default. The transaction pooler doesn't support them, so you'll get prepared statement "stmt_1" does not exist. Fix: add ?pgbouncer=true to your connection string.

FAQ

Why does my app work on Vercel but not locally?
Vercel supports IPv6. Your local machine might not. Use the pooler (6543) locally.

What's the difference between transaction and session pooler?
Transaction pooler resets after each transaction (faster). Session pooler preserves state (needed for SET commands).

Does the pooler affect performance?
~1-2ms latency per query. Negligible for most web apps.