The Adaptive Server system tables contain information that is critical to the operation of your databases. Under ordinary circumstances, you need not perform direct data modifications to system tables.
Update system tables only when you are instructed to do so by Sybase Technical Support, by an instruction in the Error Messaging and Troubleshooting Guide, or in this manual.
Before 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 that only the rows you wanted changed have been affected by the command, and that the data has been 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 dynamically built 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 prevent Adaptive Server from running, make database objects inaccessible, scramble permissions on objects, or terminate a user session. Moreover, 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 create a trigger, bind a rule, or default to a system table, you see an error message.
