pgsql: Oops, missed one fix for EquivalenceClass rearrangement.

Oops, missed one fix for EquivalenceClass rearrangement.

Now that we're expecting a mergeclause's left_ec/right_ec to persist from
the initial assignments, we can't just blithely zero these out when
transforming such a clause in adjust_appendrel_attrs. But really it should
be okay to keep the parent's values, since a child table's derived Var
ought to be equivalent to the parent Var for all EquivalenceClass purposes.
(Indeed, I'm wondering whether we couldn't find a way to dispense with
add_child_rel_equivalences altogether. But this is wrong in any case.)

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=48a1fb23900d73e7d9cb2dc0408c745cd03597a7

Modified Files
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src/backend/optimizer/prep/prepunion.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)