An event trigger checks for an event and when the event occurs, it runs the code associated with the trigger.
Publisher supports the following events: before data set is executed, after data set is executed and before a scheduled job is about to execute. There are three types of event triggers:
Before Data - Fires right before the data set is executed.
After Data - Fires right after the data engine executes all data sets and generates the XML.
Schedule Trigger - Fires when a scheduled job is triggered and before it runs.
Before data and after data triggers execute a PL/SQL function stored in a PL/SQL package in your Oracle Database. The return data type for a PL/SQL function inside the package must be a Boolean type and the function must explicitly return TRUE or FALSE.
A schedule trigger is associated with a scheduled job. It is a SQL query that executes at the time a report job is scheduled to run. If the SQL returns any data, the report job runs. If the SQL query returns no data, the job instance is skipped.
Event triggers are not used to populate data used by the bursting definition. See Add Bursting Definitions.