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Updating System Catalog Objects

The system catalog is used only for query operations—even when being used by the database administrator. Updates to the system catalog are accomplished automatically by the database server. For example, a table is created in the database when a CREATE TABLE statement is issued by a database user. The database server then places the DDL that was used to create the table in the system catalog under the appropriate system catalog table. There is never a need to manually update any table in the system catalog. The database server for each implementation performs these updates according to actions that occur within the database, as shown in Figure 21.2.

Figure 21.2. Updates to the system catalog.

Caution

Never ...