Kbase P67160: What is a Trigger
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
2/11/2004 |
|
Status: Unverified
GOAL:
What is a Trigger
FIX:
1) The general 4GL term for an event-handler procedure.
2) A piece of code that Progress executes on behalf of an application when a certain database action occurs or a certain user-interface event occurs. There are two types of triggers: database triggers and user-interface triggers.
3) A special type of stored procedure that helps ensure referential integrity for a database. Like stored procedures, triggers also contain Java source code (embedded in a CREATE TRIGGER statement) and use Progress SQL-92 Java classes. However, triggers are automatically invoked (fired) by certain SQL operations (an insert, update, or delete operation) on the trigger's target table.