ALTER GROUP SQL - Language Statements ALTER GROUP add users to a group or remove users from a group ALTER GROUP groupname ADD USER username [, ... ] ALTER GROUP groupname DROP USER username [, ... ] ALTER GROUP is used to add or remove users from a group. Only database superusers can use this command. Adding a user to a group does not create the user. Similarly, removing a user from a group does not drop the user itself. Use to create a new group and to remove a group. groupname The name of the group to modify. username Users which are to be added or removed from the group. The users must exist. ALTER GROUP Message returned if the alteration was successful. Add users to a group: ALTER GROUP staff ADD USER karl, john; Remove a user from a group: ALTER GROUP workers DROP USER beth; There is no ALTER GROUP statement in the SQL standard. The concept of roles is similar.