Re: pruning disabled for array, enum, record, range type partition keys

Amit Langote wrote:
> On Thu, Apr 19, 2018 at 12:01 AM, Alvaro Herrera
> <alvherre@alvh.no-ip.org> wrote:

> > Makes sense.  Still, I was expecting that pruning of hash partitioning
> > would also work for pseudotypes, yet it doesn't.
> 
> It does?

Aha, so it does.

While staring at this new code, I was confused as to why we didn't use
the commutator if the code above had determined one.  I was unable to
cause a test to fail, so I put that thought aside.

Some time later, after restructuring the code in a way that seemed to
make more sense to me (and saving one get_op_opfamily_properties call
for the case of the not-equals operator), I realized that with the new
code we can store the opstrategy in the PartClause instead of leaving it
as Invalid and look it up again later, so I did that.  And lo and
behold, the tests that used commutators started failing!  So I fixed
that one in the obvious way, and the tests work fully again.

Please give this version another look.  I also rewrote a couple of
comments.

I now wonder if there's anything else that equivclass.c or indxpath.c
can teach us on this topic.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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