Catalogs are searched for entries using the following methods:

1. If a catalog is specified in a macro, only that catalog is searched.
2. If the entry is identified with a qualified entry name and its first qualifier is the same as the name or alias of a user catalog, the user catalog is searched. When the entry is found, no other catalog is searched.
3. The master catalog is searched.

See z/OS DFSMS Access Method Services Commands for more detailed information.