From: Tom Lane <tgl@sss.pgh.pa.us>
To: Cedric Leong <cedricleong@gmail.com>
cc: pgsql-performance@lists.postgresql.org
Subject: Re: Date vs Timestamp without timezone Partition Key
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Comments: In-reply-to Cedric Leong <cedricleong@gmail.com>
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Date: Mon, 25 May 2020 00:48:23 -0400
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Cedric Leong <cedricleong@gmail.com> writes:
> Just in case someone is interested enough to answer this. Does anyone know
> if the performance for a date column vs a timestamp column as a partition
> key is large?

I doubt it's even measurable, at least on 64-bit machines.  You're
basically talking about 32-bit integer comparisons vs 64-bit integer
comparisons.

On a 32-bit machine it's possible that an index on a date column
will be physically smaller, so you could get some wins from reduced
I/O.  But on (most?) 64-bit machines that difference goes away too,
because of alignment restrictions.

As always, YMMV; it never hurts to do your own testing.

			regards, tom lane