Log Message:
-----------
Fix predicate-proving logic to cope with binary-compatibility cases when
checking whether an IS NULL/IS NOT NULL clause is implied or refuted by
a strict function. Per example from Dawid Kuroczko.
Backpatch to 8.2 since this is arguably a performance bug.
Tags:
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REL8_2_STABLE
Modified Files:
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pgsql/src/backend/optimizer/util:
predtest.c (r1.10.2.1 -> r1.10.2.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/predtest.c.diff?r1=1.10.2.1&r2=1.10.2.2)