Oracle笔记 十一、PL/SQL函数和触发器

--创建函数

create or replace function add_sal(sSal number)

       return number

is

begin

  if (sSal > 5000) then

    return sSal + 51;

  elsif (sSal > 3000) then

    return sSal + 111;

  else

    return sSal + 222;

  end if;

end;

select sal, add_sal(sal) from emp;

--触发器

create table deptLog(

       uName varchar2(20),

       action varchar2(20),

       dTime date

);

--创建触发器

--for each row 可以触发多条，当你的语言影响多少条记录就会触发多少次

create or replace trigger trig_dept2

  after insert or delete or update on dept2/* for each row*/

begin

  if inserting then

    insert into deptLog values(user, ‘insert‘, sysdate);

  elsif updating then

    insert into deptLog values(user, ‘update‘, sysdate);

  elsif deleting then

    insert into deptLog values(user, ‘delete‘, sysdate);

  end if; 

end;

select * from dept2;

select * from deptLog;

insert into dept2 values(55, ‘SOFTWARE‘, ‘cic‘);

update dept2 set loc = ‘go‘ where deptno in(30);

delete dept2 where deptno = 55;

--触发器

create or replace trigger trig_emp

  after update on dept for each row

begin

  update emp set emp.deptno =: new.deptno where emp.deptno = :old.deptno;

end;

update dept set deptno = 11     where deptno = 10;

select * from emp;

---语句级触发器

create or replace trigger trg_ins_dept2

before insert

on dept2

begin

     if user not in(‘SCOTT‘) then      

       raise_application_error(-20001, ‘只有SCOTT才能修改该表!‘);

     end if;

end;

禁用、启用触发器

alter trigger tgr_Name disable | enable;

alter table tableName disable all trigger | enable all trigger;