请写一个触发器，当主表A记录被删除时，同步删除子表B的记录

create trigger tri_del
for delete
on A
as
declare @aid int
select @aid=id from deleted
delete from B where B.id=@aid

这是sqlserver的触发器语句，oracle的话会有所改变。

create or replace trigger delete_ab
before delete on a
for each row
delete from b
where b.id=:old.id;
end delete_ab;

create trigger tri_del on A
for delete
as
delete B From Deleted where B.id=Deleted.id