Removing a user without dropping their data

When trying to drop a user who owns some tables or other database objects, you get the following error, and the user is not dropped:

testdb=# drop user bob;
ERROR:  role “bob” cannot be dropped because some objects depend on it
DETAIL:  owner of table bobstable
owner of sequence bobstable_id_seq

This recipe presents two solutions to this problem.

Getting ready

To modify users, you must either be a superuser or have the CREATEROLE privilege.

How to do it…

The easiest solution to this problem is to refrain from dropping the user and use the trick from a previous recipe to prevent the user from connecting:

pguser=# alter user bob nologin;
ALTER ROLE

This has the added benefit of the original owner of the table being available later, if needed, for auditing or debugging purposes (Why is this table here? Who created it?).

Then, you can assign the rights of the deleted user to a new user, using the following code:

pguser=# GRANT bob TO bobs_replacement;
GRANT

How...