Mysql使用存储过程，删除表数据

我现在有两张表A，B，两张表有外键关联，现在我想使用mysql的存储结构删除A表（关联B表）的数据，怎么写啊

http://blog.163.com/zsq303288862@126/blog/static/93745961201218112633563/
http://blog.163.com/liujun_wangyi/blog/static/110281637200922642314721/

参考
http://blog.csdn.net/mqboss/article/details/5873455

 delete from b where b.aid in (select id from a);
delete from a;

如果a表和b表有关联，需要先删除子表b的数据，然后再删除a的数据，sql如下：

delete from b where exists( select 1 from a where id = b.id);

delete from a;