The Adaptive Server system tables contain information that is critical to the operation of your databases. Under ordinary circumstances, you do not need to perform direct data modifications to system tables.
Update system tables only when you are instructed to do so by Sybase Technical Support or by an instruction in the Error Messaging and Troubleshooting Guide or in this manual.
When you update system tables, you must issue an sp_configure command that enables system table updates. While this command is in effect, any user with appropriate permission can modify a system table. Other requirements for direct changes to system tables are:
Modify system tables only inside a transaction. Issue a begin transaction command before you issue the data modification command.
Verify see that only the rows you wanted changed were affected by the command and that the data was changed correctly.
If the command was incorrect, issue a rollback transaction command. If the command was correct, issue a commit transaction command.
WARNING! Some system tables should not be altered by any user under any circumstances. Some system tables are built dynamically by system processes, contain encoded information, or display only a portion of their data when queried. Imprudent, ad hoc updates to certain system tables can make Adaptive Server unable to run, make database objects inaccessible, scramble permissions on objects, or terminate a user session. Moreover, you should never attempt to alter the definition of the system tables in any way. For example, do not alter system tables to include constraints. Triggers, defaults, and rules are not allowed in system tables. If you try to create a trigger or bind a rule or default to a system table, you will get an error message.