sql语句执行非常慢....要怎么优化啊?????????????
select   top   30   jobs.id,jobs,jobs.degree,tjsj,jobs.zt,jobs.sex,   sh.dbo.corporation.id,sh.dbo.corporation.qymc   from   rencai.dbo.jobs   ,   sh.dbo.corporation       where   (len(selectedjob)> 1   and   len(jobs)> 1   and   zt <> 1)   and   sh.dbo.corporation.id=rencai.dbo.jobs.comid       and   jobs.id   not   in(select   top   1200   jobs.id   from   rencai.dbo.jobs   where   (len(selectedjob)> 1   and   len(jobs)> 1   and   zt <> 1)   and   sh.dbo.corporation.id=jobs.comid       order   by   tjsj   desc)   order   by   tjsj   desc
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sql语句执行非常慢,甚至执行不过去,CPU占100%,...要怎么优化啊?

------解决方案--------------------
1.建立索引
2.not in 用not exists或(外连接+判断不空)代替
------解决方案--------------------
你先把这句“select top 1200 jobs.id from rencai.dbo.jobs where (len(selectedjob)> 1 and len(jobs)> 1 and zt <> 1”的结果集用临时表存放
再把not in 代换为not exists 试试
------解决方案--------------------
学习~
------解决方案--------------------
看出来了 跨库查询 建议楼主一步一步查询 仅供参考


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