Richard Guo
cc0819e78a
The check for window functions (point 4) guarded on the wrong bit: it tested UNSAFE_NOTIN_DISTINCTON_CLAUSE while setting UNSAFE_NOTIN_PARTITIONBY_CLAUSE. Each check in this loop guards on the same bit it is about to set, as an idempotency optimization, since unsafeFlags[] is accumulated across the arms of a set operation and there is no point recomputing a column's status once its bit is present. This is not a live bug. When UNSAFE_NOTIN_PARTITIONBY_CLAUSE is already set but UNSAFE_NOTIN_DISTINCTON_CLAUSE is not, the guard fails to skip targetIsInAllPartitionLists() and recomputes it, but setting the same bit again changes nothing. When UNSAFE_NOTIN_DISTINCTON_CLAUSE is already set, point 4 is skipped and UNSAFE_NOTIN_PARTITIONBY_CLAUSE is left unset; but such a column is already unsafe for pushdown via UNSAFE_NOTIN_DISTINCTON_CLAUSE, so the outcome is unchanged. To fix, test UNSAFE_NOTIN_PARTITIONBY_CLAUSE, matching the bit being set and the pattern of the surrounding checks. Back-patch to v15, where the buggy check was introduced. Author: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Tender Wang <tndrwang@gmail.com> Reviewed-by: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/CAMbWs49Q_xnF_P2QSUyDzJ34MnrO7dh-cUAaK2HJPgSgh88NcA@mail.gmail.com Backpatch-through: 15
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
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