bed3ffbf9d
rel_is_distinct_for()'s RTE_SUBQUERY branch passed only the equality operator from each join clause to query_is_distinct_for(), discarding the operator's input collation. query_is_distinct_for() then verified opfamily compatibility but never checked collations, so a DISTINCT / GROUP BY / set-op operating under one collation was trusted to prove uniqueness for a comparison performed under an unrelated collation. As with the recent fix in relation_has_unique_index_for(), this is unsound for nondeterministic collations and yields wrong query results in any optimization that consumes the proof. Fix by carrying each clause's operator input collation into query_is_distinct_for() and validating it at every check-site against the subquery target expression's collation. Back-patch to all supported branches. query_is_distinct_for() is declared in an installed header, so on stable branches the existing two-list signature is retained as a thin wrapper that forwards to a new collation-aware entry point; external callers continue to receive the historical collation-blind answer. Author: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CAMbWs4_XUUSTyzCaRjUeeahWNqi=8ZOA5Q4coi8zUVEDSBkM6A@mail.gmail.com Backpatch-through: 14 |
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| configure | ||
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| COPYRIGHT | ||
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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.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/18/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/18/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.