When you select a catalog from the contents pane and select Show Related for that object, the Show Related dialog lists any objects with first-level dependencies on that catalog. These objects can be: aliases, databases, indexes, packages, plans, synonyms, tables spaces, views. You can view second-level dependencies by selecting Show Related for each object with a first-level dependency.
Catalogs are related to all objects in the Control Center object tree. If you delete a catalog, you damage all of the objects that are represented in the catalog. SYSIBM.SYSTABLES contains a row for every table, view and alias in your system. It also tells who created it, what database it belongs to, and what table space it belongs to. Also, if a users' access privilege to a specific catalog is revoked all objects associated with that catalog are dropped for that user.
Catalog and data inconsistencies can be the result of: