create trigger biufer_employees_department_id before insert or update of department_id on employees referencing old as old_value new as new_value for each row when (new_value.department_id<>80 ) begin :new_value.commission_pct :=0; end; /
Create table foo(a number); Create trigger biud_foo Before insert or update or delete On foo Begin If user not in (‘DONNY’) then Raise_application_error(-20001, ‘You don’t have access to modify this table.’); End if; End; /
Create or replace trigger biud_employee_copy Before insert or update or delete On employees_copy Begin Insert into employees_log( Who,when) Values( user, sysdate); End; /
begin if inserting then ----- elsif updating then ----- elsif deleting then ------ end if; end; if updating(‘COL1’) or updating(‘COL2’) then ------ end if;
[試驗] 1、 修改日志表
alter table employees_log
add (action varchar2(20));
2、 修改觸發器,以便記錄語句類型。 以下是引用片段:
Create or replace trigger biud_employee_copy Before insert or update or delete On employees_copy Declare L_action employees_log.action%type; Begin if inserting then l_action:=’Insert’; elsif updating then l_action:=’Update’; elsif deleting then l_action:=’Delete’; else raise_application_error(-20001,’You should never ever get this error.’); Insert into employees_log( Who,action,when) Values( user, l_action,sysdate); End; /