ROW LEVEL TRIGGERS

EXAMPLE:
create or replace trigger mytrig
before              - -trigger time
update of sal   - -trigger statement
on emp
for each row    - -trigger level
Begin
if(:old.sal > :new.sal) then   - -trigger restriction
Raise_Apllication_Error(-20000,'sorry we cannot decrease the employee salary');
End If;
End;

NOTE: In the above example old and new are qualifiers which is used to access the values.