用触发器:
create or replace trigger Trigger_B
after delete on B
begin
delete from A where id = :old.id;
end;
create or replace trigger Trigger_B
after delete on B
begin
delete from A where id = :old.id;
end;
调试欢乐多
create or replace trigger name_tri
before delete on b
for each row
begin
delete from a where id=:new.id;
end name_tri;
SQL> create table a
2 (id varchar2(10),
3 dep varchar2(10),
4 birthday date,
5 name varchar2(10),
6 constraint pk_a primary key (id,dep,birthday))
7 /
Table created.SQL> create table b
2 (id varchar2(10),
3 dep varchar2(10),
4 birthday date,
5 sal number(10))
6 /
Table created.SQL> alter table b
2 add constraint fk_b_a foreign key (id,dep,birthday)
3 references a (id,dep,birthday)
4 on delete cascade
5 /
Table altered.
只能删除不能更新