嵌套查询经典案例

嵌套查询经典案例！！

文章来源：岚山夜话
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select [UserName],
(select count(*) from company where Comid=T1.UserName) as 招聘站,
(select count(*) from TrainOrg where OrgID=T1.UserName) as 培训机构,
(select count(*) from Train_Company Where Comid=T1.UserName) as 培训公司,
(select count(*) from Com_Class where Comid=T1.UserName) as 校园招聘,
(select count(*) from Cjoleng.dbo.CompanyInfo where CompanyID in (select [Id] from Combaseuser where [UserName]=T1.[UserName])) as 英文站
from Combaseuser T1
group by [UserName]
having count(*)>1