Catalog integrity
To ensure that the information in the catalog is always accurate, DB2® UDB for iSeries™ prevents users from explicitly changing the information in the catalog and by implicitly maintaining the information when an SQL object described in the catalog is changed.
The integrity of the catalog is maintained whether objects in the schema are changed by SQL statements, i5/OS® CL commands, System/38™ Environment CL commands, System/36™ Environment functions, or any other product or utility on a System i™ platform. For example, you can delete a table by running an SQL DROP statement, issuing an i5/OS Delete File (DLTF) CL command, issuing a System/38 Delete File (DLTF) CL command, or entering option 4 on a WRKF or WRKOBJ display. Regardless of the interface used to delete the table, the database manager removes the description of the table from the catalog when the table is deleted. The following table lists various functions and their associated effects on the catalog.
Table 1. Effects of various functions on catalogs Function Effect on the catalog Add constraint to table Information added to catalog Remove of constraint from table Related information removed from catalog Create object into schema Information added to catalog Delete of object from schema Related information removed from catalog Restore of object into schema Information added to catalog Change of object long comment Comment updated in catalog Change of object label (text) Label updated in catalog Change of object owner Owner updated in catalog Move of object from a schema Related information removed from catalog Move of object into schema Information added to catalog Rename of object Name of object updated in catalog
Parent topic:
Data integrity