Обсуждение: pgsql: Add check for syscache lookup failure inupdate_relispartition()

Add check for syscache lookup failure in update_relispartition().

Omitted in commit 05b38c7e6 (though it looks like the original blame
belongs to 9e9befac4).  A failure is admittedly unlikely, but if it
did happen, SIGSEGV is not the approved method of reporting it.

Per Coverity.  Back-patch to v11 where the broken code originated.

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/030ad0acfa5794c645a9a6093fdd3ed4d4f4788c

Modified Files
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src/backend/commands/indexcmds.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)