branch-3.0: [fix](nereids) do eliminate constant group by key in normalizeagg #49589 #50042
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…9589) ### What problem does this PR solve? Related PR: #32878 #49473 Problem Summary: SELECT IF( t.`gender` IN ('女'), ( TIMESTAMPDIFF( YEAR, NOW(), NOW() ) ), 1 ) AS x0, TIMESTAMPDIFF( YEAR, NOW(), NOW() ) AS x1 FROM t1 AS t GROUP BY x0, x1; after EliminateGroupByConstant, this sql will be rewritten to SELECT IF( t.`gender` IN ('女'), 0, 1 ) AS x0, 0 AS x1 FROM t1 AS t GROUP BY IF( t.`gender` IN ('女'), ( TIMESTAMPDIFF( YEAR, NOW(), NOW() ) ), 1 ) ; The select expression and the group by expression is different, and will report error in normalizeagg. The fix in PR #49473 may introduce another issue. Consider the following query: SELECT func2(100) FROM t GROUP BY func1(), func2(func1()); If func1() can be constant-folded to 100, then func2(func1()) will be replaced with func2(100), allowing the query to execute successfully. However, when func1() cannot be folded to 100, the query will fail. This creates an inconsistent behavior where query execution depends on whether func1() can be constant-folded or not, which is not an ideal implementation. To address this issue, this PR modifies the normalizeAgg logic to eliminate constant group by keys. With this change, the query will consistently fail regardless of whether func1() can be folded or not, ensuring more predictable behavior.
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Thank you for your contribution to Apache Doris. Please clearly describe your PR:
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run buildall |
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Cherry-picked from #49589