9e85b20da7
Consistently reset so->scanBehind at the beginning of nbtree array advancement, even during sktrig_required=false calls (calls where array advancement is triggered by an unsatisfied non-required array scan key). Otherwise, it's possible for queries to fail to return all relevant tuples to the scan given a low-order required scan key that was previously deemed "satisfied" by a truncated high key attribute value. This only happened at the point where a later non-required array scan key needed to be "advanced" once on the next leaf page (that is, once the right sibling of the truncated high key page was reached). The underlying issue was that later code within _bt_advance_array_keys assumed that the so->scanBehind flag must have been set using the current page's high key (not the previous page's high key). Any later successful recheck call to _bt_check_compare would therefore spuriously be prevented from making _bt_advance_array_keys return true, based on the faulty belief that the truncated attribute must be from the scan's current tuple (i.e. the non-pivot tuple at the start of the next page). _bt_advance_array_keys would return false for the tuple, ultimately resulting in _bt_checkkeys failing to return a matching tuple. Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp execution. Author: Peter Geoghegan <pg@bowt.ie> Discussion: https://postgr.es/m/CAH2-WzkJKncfqyAUTeuB5GgRhT1vhsWO2q11dbZNqKmvjopP_g@mail.gmail.com Backpatch: 17-, where commit 5bf748b8 first appears.
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/17/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/17/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/.