Restrictions on Triggers

To create a trigger on a table or a view, you must own the table or view, or have DBA status. For the relationship between the privileges of the trigger owner and those of other users, see Privileges to Execute Trigger Actions.

The table on which you create a trigger must exist in the current database. You cannot create a trigger on any of the following types of tables:

• A diagnostics table, a violations table, or a table in another database
• A raw table, a temporary table, or a system catalog table

Extended Parallel Server does not support triggers on a static or scratch tables, and does not support light appends on operational tables on which a trigger is defined. (Light appends are described in the IBM Informix Administrator's Guide.)

For additional restrictions on INSTEAD OF triggers on views, see Restrictions on INSTEAD OF Triggers on Views (IDS).

In DB–Access, if you want to define a trigger as part of a schema, place the CREATE TRIGGER statement inside a CREATE SCHEMA statement.

If you are embedding the CREATE TRIGGER statement in an ESQL/C program, you cannot use a host variable in the trigger definition.

You can use the DROP TRIGGER statement to remove an existing trigger. If you use DROP TABLE or DROP VIEW to remove triggering tables or views from the database, all triggers on those tables or views are also dropped.