SQL SERVER – Delete Duplicate Records

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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, DuplicateColumn3)

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