Locking for Q command codes

When a Q command code is issued for a root or dependent segment, a Q command code lock at share level is obtained for the segment. This lock is not released until a DEQ call with the same class is issued, or until commit time.

If a root segment is returned in hold status, the root lock obtained when entering the database record prevents another user with update capability from entering the database record. If a dependent segment is returned in hold status, a Q command code test lock is required. An indicator is turned on whenever a Q command code lock is issued for a database. This indicator is reset whenever the only application scheduled against the database ends. If the indicator is not set, then no Q command code locks are outstanding and no test lock is required to return a dependent segment in hold status.