Friday, June 14, 2013

Types if Triggers in Oracle Reports

There are eight report triggers.
Global triggers called the Report Triggers :
(1) Before Parameter Form
(2) After Parameter Form
(3) Before Report
(4) After Report
(5) Between Pages
Other Triggers :
(1) Validation Triggers
(2) Format Triggers
(3) Action Triggers
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(1) Before Parameter Form
Fires before the Runtime Parameter Form is displayed. From this trigger, you can access and
change the values of parameters, PL/SQL global variables, and report-level columns. (Note : If the Runtime Parameter Form is suppressed, this trigger still fires. Consequently, you can use this trigger for validation of command line parameters).


(2) After Parameter Form
Fires after the Runtime Parameter Form is displayed. Fromfires. Consequently, you can use this trigger for validation of command line parameters or other data).


(3) Before Report
Fires before the report is executed but after queries are parsed and data is fetched.


(4) Between Pages
Fires before each page of the report is formatted, except
the very first page. This trigger can be
used for customized page formatting. (Note : In the
Previewer, this trigger only fires the first time that
you go to a page. If you subsequently return to the page,
the trigger does not fire again.)


(5) After Report
Fires after you exit the Previewer, or after report output
is sent to a specified destination, such
as a file, a printer, or an Oracle*Mail userid. This
trigger can be used to clean up any initial processing
that was done, such as deleting tables. Note, however, that
this trigger always fires, whether or not
your report completed successfully.


(6) Validation Triggers
Validation Triggers are PL/SQL functions that are executed
when parameter values are
specified on the command line and when you accept the
Runtime Parameter Form. (Notice that this
means each Validation Trigger may fire twice when you
execute the report). Validation Triggers are
also used to validate the Initial Value of the parameter in
the Parameter property sheet.


(7) Format Triggers
Format Triggers are PL/SQL functions executed before the
object is formatted. The trigger can
be used to dynamically change the formatting attributes of
the object.


(8) Action Triggers
Action Triggers are PL/SQL procedures executed when a
button is selected in the Previewer.
The trigger can be used to dynamically call another report
(drill down) or execute any other PL/SQL.