关于Mysql触发器的问题

A B两表关联
A表
id(自增),
code ,
name
...
B表
id(自增),
code,
name
...
请问如何做到在删除A表数据的同时删除B表中相同的数据？

 DELIMITER $$ 
create trigger DelTableB_ByCode before delete
on Table_A for each row
begin
delete
from Table_B
where Table_B.code =old.code ;
end$$
delimiter ;

用SQL啊，where in