fix(parser): Apply HAVING before window functions - #1842
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Summary:
A window function nested in a larger expression saw the groups HAVING had already removed, so its aggregate covered rows the query had filtered out:
SELECT a, count(*) / sum(count(*)) OVER (PARTITION BY a)
FROM t GROUP BY a, b HAVING count(*) > 1
The denominator summed every group, not just the ones with more than one row, making each fraction too small. A window that is the whole select item was already ordered correctly; only one nested in an expression was affected.
The HAVING filter is now emitted before the nested-window projection rather than after it, so the window reads the filtered rows.
Differential Revision: D119035291
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amitkdutta
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Sep 7, 2026
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This pull request has been merged in 6d65c07. |
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Summary:
A window function nested in a larger expression saw the groups HAVING had already removed, so its aggregate covered rows the query had filtered out:
The denominator summed every group, not just the ones with more than one row, making each fraction too small. A window that is the whole select item was already ordered correctly; only one nested in an expression was affected.
The HAVING filter is now emitted before the nested-window projection rather than after it, so the window reads the filtered rows.
Differential Revision: D119035291