The USAGE privilege is required to perform any action on a database object. It does not grant any abilities by itself but is necessary alongside other permissions. For a user to perform an action on a schema object, they must have the USAGE privilege on that schema in addition to the specific action privilege. This requirement can be satisfied by being an admin, having the USAGE privilege on the schema or catalog, being in a group with the USAGE privilege, or being the owner of the schema or in a group that owns the schema. Even the owner of an object within a schema needs the USAGE privilege to use it.