dfd8e6c73e
GIN and GiST indexes utilizing pg_trgm's opclasses store sorted trigrams within index tuples. When comparing and sorting each trigram, pg_trgm treats each character as a 'char[3]' type in C. However, the char type in C can be interpreted as either signed char or unsigned char, depending on the platform, if the signedness is not explicitly specified. Consequently, during replication between different CPU architectures, there was an issue where index scans on standby servers could not locate matching index tuples due to the differing treatment of character signedness. This change introduces comparison functions for trgm that explicitly handle signed char and unsigned char. The appropriate comparison function will be dynamically selected based on the character signedness stored in the control file. Therefore, upgraded clusters can utilize the indexes without rebuilding, provided the cluster upgrade occurs on platforms with the same character signedness as the original cluster initialization. The default char signedness information was introduced in 44fe30fdab6, so no backpatch. Reviewed-by: Noah Misch <noah@leadboat.com> Discussion: https://postgr.es/m/CB11ADBC-0C3F-4FE0-A678-666EE80CBB07%40amazon.com
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/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/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/.