Types of Triggers in Reports: -

* Report Triggers * Data Triggers * Layout Triggers

Report Triggers: -

After Parameter form Trigger.
After Report Trigger
Before parameter form Trigger
Before Report Trigger.
Between Pages Trigger
+ Firing Sequence
* Before Parameter form Trigger
- Fires before the runtime parameter form is displayed.
- The parameter values can be accessed and changed.
* After Parameter form Trigger.
- Fires after the runtime parameter form is displayed.
- The parameters can be accessed and their values can be checked.
* Before Report Trigger
- Fires before the reports is executed but after the queries are passed and data is fetched.
* Between Pages Trigger.
- Fires between each page of the report are formatted, except the very first pages.
- This is used for customized page formatting.
* After Report Trigger
- Fires after exiting from the run time premier or after report output is sent to a specified
destination. (File, Printer, Mail id etc….)
- This is used to clean up any initial processing that was done such as deleting the tables.
- This Trigger always fires irrespective of success or failure of the report.

DATA TRIGGERS:-

* Ref Cursor Query.
- This uses PL/SQL to fetch data for the report.
- In this a PL/SQL function need to be specified to return a cursor value from a cursor variable.
-
* Group Filter:
This is PL/SQL function that determines which records to be included in a group in the
property are PL/SQL.
- The function must return a BOOLEAN value.
True ……. Includes the current record in the report.
False ……. Excludes the current record from the report.
* Formula
- These are PL/SQL functions that populate formula or place holder columns.
* Validation Trigger
- These are also PL/SQL functions that are executed when parameter values are specified on the
command line and when the runtime parameter form is accepted.
- Are also used to validate the initial value property of the parameter.

 Layout Triggers :- 

* Format Trigger.
- These are PL/SQL functions executed before the object is formatted.
- Used to dynamically change the formatting attributes of the object.
* Action Trigger
- These are PL/SQL procedures executed when a button is selected in the run time
Pre-viewer.
- This can be used to dynamically call another report or execute any other PL/SQL.