SQL找出和删除一个表的重复记录
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SELECT Column1, Column2,Column3,Column4 FROM T_Table GROUP BY Column1, Column2 ,Column3,Column4 HAVING Count(1)>1
DELETE T_Table
WHERE Id IN (SELECT a.Id
FROM T_Table a
WHERE EXISTS (
SELECT b.Id
FROM T_Table b
WHERE b.Column1 = a.Column1
AND b.Column2 = a.Column2
AND b.Column3 = a.Column3
AND b.Column4 = a.Column4
AND b.Id<a.Id
))