ALTER GROUP name ADD USER username [, ... ] ALTER GROUP name DROP USER username [, ... ]
The name of an existing group to alter.
The names of existing users you wish to add or remove from the specified group. Multiple names are delimited by commas.
Database superusers can use the ALTER GROUP command to add and remove specified users from a group. As groups can be allocated privileges, adding members to a group grants those privileges by proxy. Users must exist before they can be added to a group. Dropping a user from a group does not drop a user from the system.
Use CREATE GROUP to create a new group and DROP GROUP to remove a group. Use GRANT and REVOKE to manage privileges on a group.
The following example adds the PostgreSQL database users jessica and william to the sales group:
booktown=# ALTER GROUP sales ADD USER jessica, william; ALTER
The next example removes the user jessica from the sales group:
booktown=# ALTER GROUP sales DROP USER jessica; ALTER