sql Left Join 右表取一条数据,三种方式

发布时间:2023-07-23 11:02:43 阅读:809次

一、(Oracle中已驗證OK)

left join

(select l.* from
(select RealName,CompanyId,row_number() over (partition by CompanyId order by id desc) as rownum1 from vm_User WHERE IsAdmin=1) l
where l.rownum1 = 1 ) w

二、left join (select MAX(RealName),CompanyId, from vm_User GROUP BY CompanyId) W

三、

用OUTER APPLY
select b.* FROM a表 a
OUTER APPLY
(select TOP(1) * from b表 WHERE [Name] = a.[AName] ORDER BY BNo desc) b

原文链接:https://blog.csdn.net/sinat_36500530/article/details/105116381

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