orca: fallback to Postgres optimizer on cross-slice replicated CTE Consumer#375
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Test doesn't reproduce the error without the patch
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Increase ss_t1 to 40000 rows and simplify the query so that ORCA picks the cross-slice plan where the unpaired-Consumer path is exercised. With the previous 10-row input, plan costs favored the same-slice variant and the test would silently pass even without the fix. Cherry-picked from #375 (de87aaf).
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Increase ss_t1 to 40000 rows and simplify the query so that ORCA picks the cross-slice plan where the unpaired-Consumer path is exercised. With the previous 10-row input, plan costs favored the same-slice variant and the test would silently pass even without the fix. Cherry-picked from #375 (de87aaf).
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…nsumer. orca: fallback to Postgres optimizer on cross-slice replicated CTE Consumer Inspired by greengage 51fe92e: before Expr->DXL translation, walk the physical tree and track which slice each CTE Producer and Consumer lives on. If a Consumer is on a different slice than its Producer and the Producer's distribution is replicated, force a fallback to the Postgres optimizer. The replicated filter is essential: ordinary cross-slice CTE plans (non-replicated Producer with Gather/Redistribute Consumer) are a normal ORCA pattern and must not trigger fallback. 51fe92e doesn't trigger when a CTE over a replicated table is referenced from a scalar subquery, so the query hangs. This commit replaces the single-point check with a whole-tree walker that catches both cases. Tests: bring the original qp_orca_fallback case from 51fe92e and add a scalar-subquery reproducer in shared_scan guarded by statement_timeout.
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Co-authored-by: Andrey Sokolov <sokolov.andrey.yurevich@gmail.com>
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…nsumer (#375) Inspired by greengage 51fe92e: before Expr->DXL translation, walk the physical tree and track which slice each CTE Producer and Consumer lives on. If a Consumer is on a different slice than its Producer and the Producer's distribution is replicated, force a fallback to the Postgres optimizer. The replicated filter is essential: ordinary cross-slice CTE plans (non-replicated Producer with Gather/Redistribute Consumer) are a normal ORCA pattern and must not trigger fallback. 51fe92e doesn't trigger when a CTE over a replicated table is referenced from a scalar subquery, so the query hangs. This commit replaces the single-point check with a whole-tree walker that catches both cases. Tests: bring the original qp_orca_fallback case from 51fe92e and add a scalar-subquery reproducer in shared_scan guarded by statement_timeout. cherry-pick from 3a9aebf
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…nsumer (#375) Inspired by greengage 51fe92e: before Expr->DXL translation, walk the physical tree and track which slice each CTE Producer and Consumer lives on. If a Consumer is on a different slice than its Producer and the Producer's distribution is replicated, force a fallback to the Postgres optimizer. The replicated filter is essential: ordinary cross-slice CTE plans (non-replicated Producer with Gather/Redistribute Consumer) are a normal ORCA pattern and must not trigger fallback. 51fe92e doesn't trigger when a CTE over a replicated table is referenced from a scalar subquery, so the query hangs. This commit replaces the single-point check with a whole-tree walker that catches both cases. Tests: bring the original qp_orca_fallback case from 51fe92e and add a scalar-subquery reproducer in shared_scan guarded by statement_timeout. cherry-pick from 3a9aebf
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orca: fallback to Postgres optimizer on cross-slice replicated CTE Consumer
Inspired by greengage 51fe92e: before Expr->DXL translation,
walk the physical tree and track which slice each CTE Producer
and Consumer lives on. If a Consumer is on a different slice
than its Producer and the Producer's distribution is replicated,
force a fallback to the Postgres optimizer.
The replicated filter is essential: ordinary cross-slice CTE plans
(non-replicated Producer with Gather/Redistribute Consumer) are a
normal ORCA pattern and must not trigger fallback.
51fe92e doesn't trigger when a CTE over a replicated table is
referenced from a scalar subquery, so the query hangs. This commit
replaces the single-point check with a whole-tree walker that
catches both cases.
Tests: bring the original qp_orca_fallback case from 51fe92e and add
a scalar-subquery reproducer in shared_scan guarded by
statement_timeout.