Connect with psql

Postgres · Reference cheat sheet

📋 Overview

psql is the primary admin CLI: run SQL, inspect catalogs with meta-commands, and script automation with variables and \copy.

Connection form	Example
URL	`postgres://user:pass@host:5432/db`
Flags	`psql -h host -U user -d db`
`.pgpass`	Password file for non-interactive auth
`PG*` env	`PGHOST`, `PGUSER`, `PGDATABASE`

Connect and list tables:

psql -h 127.0.0.1 -U app -d app

\dt
\d users

Run file / one-shot:

psql "$DATABASE_URL" -f migrate.sql
psql "$DATABASE_URL" -c "SELECT now();"

CSV copy out:

\copy (SELECT id, email FROM users) TO 'users.csv' CSV HEADER

Passwords on the command line leak via process lists — prefer .pgpass or env URL carefully.
\d shows one schema search_path view — check \dn / qualify schema names.
Interactive transactions left open (BEGIN without COMMIT) block others.