respect nulls
clauseThe last_value(…)
window function evaluates its argument using the last row defined by the over
clause:
SELECT LAST_VALUE(<expr>) OVER (ORDER BY …)
FROM …
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
The last_value()
window function is defined in ISO/IEC 9075:2016-2 as part of optional feature T617, “FIRST_VALUE and LAST_VALUE functions”.
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