select distinct substring(stu_class,1,4) grade
from
(select *
from stu_info a inner join selcou_info b
on a.stu_id=b.stu_id
where score_time='43242') ttwhere stu_class like @a
from
(select *
from stu_info a inner join selcou_info b
on a.stu_id=b.stu_id
where score_time='43242') ttwhere stu_class like @a
from (select *
from stu_info a inner join selcou_info b
on a.stu_id=b.stu_id
where score_time='43242') a
where stu_class like @a
from
(select *
from stu_info a inner join selcou_info b
on a.stu_id=b.stu_id
where score_time='43242')
where stu_class like @a
from
(select *
from stu_info a inner join selcou_info b
on a.stu_id=b.stu_id
where score_time='43242') ttwhere stu_class like @a 这句不行吗
from stu_info a
inner join selcou_info b on a.stu_id =b.stu_id
where a.stu_class like @a and score_time ='43242'