The structure of every IQ database is described in a number of system tables.
The Entity-Relationship diagram on the next page shows all the system tables and the foreign keys connecting the system tables.
The system tables are owned by the SYS user ID. The contents of these tables can only be changed by the database system. Thus, the UPDATE, DELETE, and INSERT commands cannot be used to modify the contents of these tables. Further, the structure of these tables cannot be changed using the ALTER TABLE and DROP commands.
