第1个sql内容如下:
select * from a
where a.a1 in
(select b.b1 from b
where a.a1=b.b1
and a.a2=b.b2
and a.a3 between b.b3 and b.b4
)和第2个sql内容如下:
select * from a
where (a.a1,a.a2) in
(select b.b1,b.b2 from b
where a.a1=b.b1
and a.a2=b.b2
and a.a3 between b.b3 and b.b4
)这两个sql文的执行结果是否一样,或者说,子查询里的条件非常复杂,但in的项目只要有任意一个关联,就可以得到正常结果。
select * from a
where a.a1 in
(select b.b1 from b
where a.a1=b.b1
and a.a2=b.b2
and a.a3 between b.b3 and b.b4
)和第2个sql内容如下:
select * from a
where (a.a1,a.a2) in
(select b.b1,b.b2 from b
where a.a1=b.b1
and a.a2=b.b2
and a.a3 between b.b3 and b.b4
)这两个sql文的执行结果是否一样,或者说,子查询里的条件非常复杂,但in的项目只要有任意一个关联,就可以得到正常结果。
解决方案 »
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