去除重复数据
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这是库中数据,我以C_CaseID,C_ModuleName分组,结果是三条,但现在我还想要得到C_ID,抓破头皮得不到,请各位帮我看看要怎么写这sql
------解决方案--------------------
select *
from
(
select *,ROW_NUMBER() OVER(PARTITION BY C_CaseID,C_ModuleName ,ORDER BY C_ID) rn
from tb
) t
where rn=1
------解决方案--------------------select MAX(convert(varchar(36),id)),C_CaseID,C_ModuleName from tb group by C_CaseID,C_ModuleName