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SQL SERVER - Delete Duplicate Records - Rows

Posted By :Srinivas Challa      Posted Date :18/06/2009   Points :10   Category: SQL Query    URL: http://www.challadotnetfaq.blogspot.com/
    


 

Following code is useful to delete duplicate records. The table must have identity column, which will be used to identify the duplicate records. Table in example is has ID as Identity Column and Columns which have duplicate data are DuplicateColumn1, DuplicateColumn2 and DuplicateColumn3.

DELETE
FROM
MyTable
WHERE ID NOT IN
(
SELECT MAX(ID)
FROM MyTable
GROUP BY DuplicateColumn1, DuplicateColumn2, DuplicateColumn2)


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