Avoid trying to fetch metapage of an SPGist partitioned index. This is necessary when spgcanreturn() is invoked on a partitioned index, and the failure might be reachable in other scenarios as well. The rest of what spgGetCache() does is perfectly sensible for a partitioned index, so we should allow it to go through.
I think the main takeaway from this is that we lack sufficient test coverage for non-btree partitioned indexes. Therefore, I added simple test cases for brin and gin as well as spgist (hash and gist AMs were covered already in indexing.sql). Per bug #18256 from Alexander Lakhin. Although the known test case only fails since v16 (3c569049b), I've got no faith at all that there aren't other ways to reach this problem; so back-patch to all supported branches. Discussion: https://postgr.es/m/18256-0b0e1b6e4a620...@postgresql.org Branch ------ REL_14_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/375f441bd19c0e747affbaa8a40203428411f5df Modified Files -------------- src/backend/access/spgist/spgutils.c | 29 +++++++++++++++---------- src/test/regress/expected/indexing.out | 39 ++++++++++++++++++++++++++++++++++ src/test/regress/sql/indexing.sql | 20 +++++++++++++++++ 3 files changed, 77 insertions(+), 11 deletions(-)