Can I use… last_value(…) ignore nulls


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  1. Non-standard alternative: last_value(<expr>, 'ignore nulls')
  2. Non-standard alternative: last_value(<expr> ignore nulls)

The last_value(…) window function with the ignore nulls clause evaluates its argument in the rows defined by the over clause in reverse order and returns the first non-null value (if any).

SELECT LAST_VALUE(<expr>) IGNORE NULLS OVER (ORDER BY …)
  FROM …

Default Framing Applies

If there is no explicit framing clause the following default applies:

RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW

That means, the last_value() function cannot see beyond the ties to the current row. Open the frame to bring the last row into reach:

ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING

Normative References

The last_value() ignore nulls is defined in ISO/IEC 9075:2016-2 as part of optional feature T617, “FIRST_VALUE and LAST_VALUE functions”.

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