From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <david.rowley@2ndquadrant.com>
cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Performance improvement for joins where outer side is unique
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Comments: In-reply-to David Rowley <david.rowley@2ndquadrant.com>
 message dated "Mon, 24 Aug 2015 12:50:13 +1200"
Date: Sun, 23 Aug 2015 22:29:37 -0400
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David Rowley <david.rowley@2ndquadrant.com> writes:
> On 24 August 2015 at 12:19, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I am not exactly convinced that this behavior needs to be visible in
>> EXPLAIN output at all, but if it does, it should be a separate field.

> I have to admit I don't much like it either, originally I had this as an
> extra property that was only seen in EXPLAIN VERBOSE.

Seems like a reasonable design from here.  (Note that for non-text output,
I'd say the field should come out unconditionally.  We only care about
abbreviating in text mode.)

			regards, tom lane


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