我将我写的详细的过程给lz讲下撒: (1)创建deptment表 create table deptment(id varchar2(10) primary key,name varchar2(10)not null); (2)创建emp表,如下 create table emp(eid varchar2(10),salary number(8,2),constraint fk_eid foreign key(eid)references deptment(id)); (3)建立级联触发器,语句如下 create or replace trigger del(这个是触发器的名字,可随便取撒) after delete on deptment for each row --这一行表示这是个行级触发器哦 delete from emp where eid=:old.id; end del; / lz只要给deptment表和emp表先插入数据再创建这个触发器,然后写下面语句就可以知道这个触发器的功能了 delete from deptment where id='001';(假设deptment和emp表都有id为001的数据) select * from emp; 这个时候你会发现emp表中的eid='001'的数据也没了!!!
create or replace trigger del(这个是触发器的名字,可随便取撒) after delete on deptment --------这里应该是beforefor each row --这一行表示这是个行级触发器哦 delete from emp where eid=:old.id; end del;
create or replace trigger del(这个是触发器的名字,可随便取撒) after delete on deptment --------这里应该是beforefor each row --这一行表示这是个行级触发器哦 delete from emp where eid=:old.id; end del;
create or replace trigger del(这个是触发器的名字,可随便取撒) after delete on deptment --------这里应该是before for each row --这一行表示这是个行级触发器哦 delete from emp where eid=:old.id; end del;
(1)创建deptment表
create table deptment(id varchar2(10) primary key,name varchar2(10)not null);
(2)创建emp表,如下
create table emp(eid varchar2(10),salary number(8,2),constraint fk_eid foreign key(eid)references deptment(id));
(3)建立级联触发器,语句如下
create or replace trigger del(这个是触发器的名字,可随便取撒)
after delete on deptment
for each row --这一行表示这是个行级触发器哦
delete from emp where eid=:old.id;
end del;
/
lz只要给deptment表和emp表先插入数据再创建这个触发器,然后写下面语句就可以知道这个触发器的功能了
delete from deptment where id='001';(假设deptment和emp表都有id为001的数据)
select * from emp;
这个时候你会发现emp表中的eid='001'的数据也没了!!!
after delete on deptment --------这里应该是beforefor each row --这一行表示这是个行级触发器哦
delete from emp where eid=:old.id;
end del;
after delete on deptment --------这里应该是beforefor each row --这一行表示这是个行级触发器哦
delete from emp where eid=:old.id;
end del;
after delete on deptment --------这里应该是before
for each row --这一行表示这是个行级触发器哦
delete from emp where eid=:old.id;
end del;