Delete duplicate records from table ( sql server )

SQL Delete duplicate records

--columnField1 is the field you're looking for duplicates in
--columnField2 orderby, optional, for example a datetime stamp and you want to keep the latest record 
WITH AllRecords_CTE
AS 
(
  SELECT columnField1,
	 ROW_NUMBER() over (PARTITION BY columnField1 ORDER BY columnField2 DESC) AS [rn]
  FROM #AllRecords 
)
DELETE AllRecords_CTE
WHERE [rn] > 1