An upcoming patch requires this cache so that it can track updates in the pg_extension catalog. So far though, the EXTENSIONOID cache only exists in v18 and up (see 490f869d9). We can add it in older branches without an ABI break, if we are careful not to disturb the numbering of existing syscache IDs. In v16 and before, that just requires adding the new ID at the end of the hand-assigned enum list, ignoring our convention about alphabetizing the IDs. But in v17, genbki.pl enforces alphabetical order of the IDs listed in MAKE_SYSCACHE macros. We can fake it out by calling the new cache ZEXTENSIONOID. Note that adding a syscache does change the required contents of the relcache init file (pg_internal.init). But that isn't problematic since we blow those away at postmaster start for other reasons. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Noah Misch <noah@leadboat.com> Security: CVE-2026-2004 Backpatch-through: 14-17
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/.