SELECT n
, x
, LEAD(x) IGNORE NULLS OVER(ORDER BY n)
, LAG (x) IGNORE NULLS OVER(ORDER BY n)
FROM (VALUES (0, 'A'), (1, null), (2, 'Z')) t(n,x)| n | x | LEAD(x) IGNORE NULS OVER(ORDER BY n) | LAG(x) IGNORE NULS OVER(ORDER BY n) |
|---|---|---|---|
| 0 | A | Z | |
| 1 | Z | A | |
| 2 | Z | A |
T616, “Null treatment option for LEAD and LAG functions” is defined as optional feature in ISO/IEC 9075-2:2023. It first appeared in SQL:2011.
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