SqlServer_删除重复行只保留一条记录

前提：相同的数据重复往数据库写入，导致存在仅主键Id不同的重复数据，现在需要去除重复数据，仅保留重复数据中Id最大的一条

思路：

1、找出存在重复数据的记录，并取重复数据中最大的Id值

2、删除记录中不包含最大Id值的记录

实现：

DELETE FROM [Log_IIS].[dbo].[IISLog_table]

WHERE id not in

(select MAX(Id) from [IISLog_table] group by [RequestTime]

,[LogFilename]

,[LogRow]

,[date]

,[time]

,[cIp]

,[csUsername]

,[sSitename]

,[sComputername]

,[sIp]

,[sPort]

,[csMethod]

,[csUriStem]

,[csUriQuery]

,[scStatus]

,[scSubstatus]

,[scWin32Status]

,[scBytes]

,[csBytes]

,[timeTaken]

,[csVersion]

,[csHost]

,[csUserAgent]

,[csCookie]

,[csReferer]

,[sEvent]

,[sProcessType]

,[sUserTime]

,[sKernelTime]

,[sPageFaults]

,[sTotalProcs]

,[sActiveProcs]

,[sStoppedProcs] having count(*) > 1)   

来自为知笔记(Wiz)

时间： 2024-10-07 11:34:04

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