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DECLARE @Sample AS VARCHAR(6) = '115351'
SELECT CONVERT(VARCHAR(10), DATEADD(DAY, CONVERT(INT, @Sample) - ((1000*(CONVERT(INT, @Sample)/1000)))-1, DATEADD(YEAR, CONVERT(INT, @Sample/1000), '1 Jan 1900')), 103) AS Result
| Result |
|---|
| 17/12/2015 |