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 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)
If there is no identity column then
Add Identity Col and perform the operation displayed above and drop Identity Col.
DELETE
FROM MyTable
WHERE ID NOT IN
(
SELECT MAX(ID)
FROM MyTable
GROUP BY DuplicateColumn1, DuplicateColumn2, DuplicateColumn3)
If there is no identity column then
Add Identity Col and perform the operation displayed above and drop Identity Col.
No comments:
Post a Comment