pg_upgrade: Check for arrays over system types with auto-assigned OIDs Array values embed their element type's OID, and pg_upgrade does not rewrite user data. The OIDs of information_schema domains can vary between major versions, so a stored array over one (e.g. by aggregating an information_schema query into a table) comes through the upgrade with at best a dangling element OID. Whole-array reads and pg_dump of the upgraded cluster then fail with "cache lookup failed for type N". Worst case, the OID has been reassigned, leading to values being misread instead.
The data type checks miss this because nothing flags the domain itself: domain storage is just the base type, so the recursive expansion in data_type_check_query() never reaches the array type. Add a check for arrays whose element type OID was assigned by genbki.pl or initdb, including anything in information_schema in case it was dropped and reloaded. The scenarios that hit this are fairly contrived, which probably explains the lack of field reports, so no backpatch for now. Reviewed-by: Chengpeng Yan <[email protected]> Discussion: https://postgr.es/m/CANWCAZbusXHWWSq_9NpxtOGvR=m5mh4uj+wo0f1_rtc0ume...@mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/77f54eb07488341025073a370f6e381a6ee05e04 Modified Files -------------- src/bin/pg_upgrade/check.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)
