How Is the System Catalog Created?

The system catalog is either created automatically with the creation of the database, or by the database administrator immediately following the creation of the database. For example, a set of predefined, vendor-provided SQL scripts in Oracle are executed, which builds all the database tables and views in the system catalog that are accessible to a database user. The system catalog tables and views are system-owned and not specific to any one schema. In Oracle, for example, the system catalog owner is a user account called SYS, which has full authority in the database. In Sybase, the system catalog for the SQL server is located in the master database.