Create a new table EMPTEN same as standard EMP Table.
Create a database trigger on the table EMPTEN by using the following code
create trigger trig1 before insert or update on empten for each row begin if :NEW.ename is null then raise_application_error ( -20101, 'Employee name cannot be blank'); end if; end; /
Create a new form based on table EMPTEN by using Data block wizard and layout wizard.
Save the form with the name EMP_TEN.fmb
Compile the form.
Run the form.
Click on Execute Query, As we know first record is displayed
Remove the ename and try to save the record, we get the error.
The database trigger (trig1 ) which we have created is stopping the record to be updated.
Help Display error is used to look at the error messages of the trigger.