pgsql: Teach predtest.c that "foo" implies "foo IS NOT NULL". - Mailing list pgsql-committers

Teach predtest.c that "foo" implies "foo IS NOT NULL".

Per complaint from Peter Holzer.  It's useful to cover this special case,
since for a boolean variable "foo", earlier parts of the planner will have
reduced variants like "foo = true" to just "foo", and thus we may fail
to recognize the applicability of a partial index with predicate
"foo IS NOT NULL".

Back-patch to 9.5, but not further; given the lack of previous complaints
this doesn't seem like behavior to change in stable branches.

Branch
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REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/8dccf030e884ea8c723275a070acf8a8ed1eebe1

Modified Files
--------------
src/backend/optimizer/util/predtest.c |    4 ++++
1 file changed, 4 insertions(+)