PostgreSQL 18 cheatsheet

PostgreSQL 18: Inspecting the database

9 common PostgreSQL 18 tasks.

List databases

Show every database on the server. Run \l inside psql or use the flag from the shell.

psql -U postgres -l

Connect to another database from inside psql.

\c mydb

Show the tables in the current schema search path.

\dt

Show a table's columns, types, indexes and constraints.

\d users

Show the schemas in the current database.

\dn

Show database roles and their attributes.

\du

Show each row as a vertical list, which is easier to read for wide tables.

\x

Toggle timing output after each statement.

\timing

Show the on-disk size of a database in a readable unit.

SELECT pg_size_pretty(pg_database_size('mydb'));