PostgreSQL Tutorial: Show Tables

Summary: in this tutorial, you will learn how to show tables in PostgreSQL using psql tool and pg_catalog schema.

Table of Contents

If you are coming from MySQL, you may want to use the popular SHOW TABLES statement that displays all tables in a specific database.

PostgreSQL does not support the SHOW TABLES statement directly but provides you with an alternative.

Showing tables from PostgreSQL using psql

First, connect to PostgreSQL using the psql tool.

$ psql -U postgres -W

The -U flag stands for the user and -W option requires you to provide the password. In this command, you use the postgres user to log in to the PostgreSQL database server.

Second, enter the password for the user postgres and press the Enter keyboard:

Password for user postgres:
postgres=#

Third, switch to a database e.g.., dvdrental:

postgres=# \c dvdrental
You are now connected to database "dvdrental" as user "postgres".

Note that you can connect to a specific database when you log in to the PostgreSQL database server:

$ psql -U postgres -d dvdrental

In this command, the -d flag means database. In this command, you connect to the dvdrental database using the postgres user.

Third, use the \dt command from the PostgreSQL command prompt to show tables in the dvdrental database:

postgres=# \dt

Output:

To get more information on tables, you can use the \dt+ command. It will add the size and description columns:

postgres=# \dt+

Showing tables using pg_catalog schema

Another way to show tables in PostgreSQL is to use the SELECT statement to query data from the PostgreSQL catalog as follows:

SELECT *
FROM pg_catalog.pg_tables
WHERE schemaname != 'pg_catalog' AND 
    schemaname != 'information_schema';

In this query, we used a condition in the WHERE clause to filter system tables. If you omit the WHERE clause, you will get many tables including the system tables.

Summary

• Use the \dt or \dt+ command in psql to show tables in a specific database.
• Use the SELECT statement to query table information from the pg_catalog.pg_tables catalog.