用全外连接做就可以,全外连接会把A表和B表中所有的行都会查询出来,关键字是full outer join。sql语句如下:
select a.xm as '姓名', ISNULL(sx, 0) as '数学', ISNULL(yw, 0) as '语文' from a full outer join b on a.xm=b.xm