Postgres: To Retrieve list of users

 to retrieve a list of users from the pg_user table, which contains information about database users:

SELECT usename AS username FROM pg_user;

SELECT rolname FROM pg_roles;

This query will return a list of usernames from your PostgreSQL database. If you need more details about each user, you can modify the query to include additional columns:

SELECT usename AS username, usesysid AS user_id, usecreatedb AS can_create_db, usesuper AS is_superuser  FROM pg_user;

SELECT usename AS role_name, CASE WHEN usesuper AND usecreatedb THEN CAST('superuser, create database' AS pg_catalog.text) WHEN usesuper THEN CAST('superuser' AS pg_catalog.text) WHEN usecreatedb THEN CAST('create database' AS pg_catalog.text) ELSE CAST('' AS pg_catalog.text) END role_attributesFROM pg_catalog.pg_userORDER BY role_name desc;