Re: BUG #18256: spgGetCache() attempts to read to read invalid file for index attached to partitioned table

PG Bug reporting form <noreply(at)postgresql(dot)org> writes:
> The following query:
> CREATE TABLE t(a int, b text) PARTITION BY RANGE (a);
> CREATE INDEX idx ON t USING spgist(b);
> SELECT * FROM t;

> produces an unexpected error:
> ERROR: could not open file "pg_tblspc/0/PG_16_202307071/0/0": No such file
> or directory

Thanks for the report. It looks like we could work around this by
teaching spgGetCache to not try to get the lastUsedPages info for
a partitioned index. (The rest of what it does is still valid for
partitioned indexes.) I wonder though if there are any other similar
bugs --- obviously, non-btree partitioned indexes haven't been
tested sufficiently.

> Reproduced on REL_16_STABLE (starting from 3c569049b) .. master.

It should be possible to exhibit similar problems long before 3c569049b,
I would guess.

regards, tom lane