Mysql子查询IN中使用LIMIT应用示例

这两天项目里出了一个问题，limit使用后报错。

需求是这样的，我有3张表，infor信息表，mconfig物料配置表，maaply物料申请表，要求是读出申请表中哪些人申请哪些物料

于是我先是这样写的：

select infor.name,infor.phone,infor.add,
mconfig.mname,mapply.acount,from_unixtime(mapply.atime,'%y-%m-%d') as 'atime'
from mapply right join infor on mapply.uid = infor.uid inner join mconfig on mapply.mid = mconfig.mid
where mapply.aid
in (
select aid
from `mapply` where state = $state
order by `atime` , `uid` desc
limit 0,10
)

结果报错了

当时没注意报的什么错误，只是看到limit什么的错误，于是改了下代码

select infor.name,infor.phone,infor.add,
mconfig.mname,mapply.acount,from_unixtime(mapply.atime,'%y-%m-%d') as 'atime'
from mapply right join infor on mapply.uid = infor.uid inner join mconfig on mapply.mid = mconfig.mid
where mapply.aid
in (
select aid
from `mapply` where state = $state
order by `atime` , `uid` desc
)
<pre name="code" class="sql">limit 0,10</pre>

这样没有报错，莫离以为ok了，但是运行后发现，数据有问题

和单纯的读出申请表的内容不一样，才发现limit的位置放错了，于是又把limit发在in里，结果报错如下

this version of mysql doesn't yet support ‘limit & in/all/any/some subquery'

细看才知道，in里不支持limit。那怎么办呢？

于是度娘后得知，在in里再使用一张临时表，把需要的内容先查出来，

修改后代码如下：

select infor.name,infor.phone,infor.add,
mconfig.mname,mapply.acount,from_unixtime(mapply.atime,'%y-%m-%d') as 'atime'
from mapply right join infor on mapply.uid = infor.uid inner join mconfig on mapply.mid = mconfig.mid
where mapply.aid
in (
select aid
from （select `aid` from `mapply` where state = $state
order by `atime` , `uid` desc
limit 0,10）as `tp`
)

运行后，问题解决~~~