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WITH yourTable AS (
SELECT [actualDate]
FROM (
VALUES ('2021-09-20')
, ('2021-09-21')
, ('2021-09-22')
, ('2021-09-23')
, ('2021-09-24')
, ('2021-09-25')
, ('2021-09-26')
, ('2021-09-27')
, ('2021-09-28')
) as t (actualDate)
)
SELECT
actualDate,
1 + DATEDIFF(day, CAST(GETDATE() AS date), actualDate) dateOffset
FROM yourTable
ORDER BY actualDate;
| actualDate | dateOffset |
|---|---|
| 2021-09-20 | -610 |
| 2021-09-21 | -609 |
| 2021-09-22 | -608 |
| 2021-09-23 | -607 |
| 2021-09-24 | -606 |
| 2021-09-25 | -605 |
| 2021-09-26 | -604 |
| 2021-09-27 | -603 |
| 2021-09-28 | -602 |