From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marc Slemko <marcs@znep.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: performance of SELECT * much faster than SELECT <colname> with large offset
Date: Thu, 02 Oct 2014 22:39:37 -0400
Message-ID: <10064.1412303977@sss.pgh.pa.us> (raw)
In-Reply-To: <CAN1FPGN1ynBj3m1DMszc9MEYVj41S96OMy8-Q1cgKMGxv482SA@mail.gmail.com>
References: <CAN1FPGN1ynBj3m1DMszc9MEYVj41S96OMy8-Q1cgKMGxv482SA@mail.gmail.com>
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Marc Slemko <marcs@znep.com> writes:
> I ran into this oddity lately that goes against everything I thought I
> understood and was wondering if anyone had any insight.
SELECT * avoids a projection step ... see ExecAssignScanProjectionInfo.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, marcs@znep.com
Subject: Re: performance of SELECT * much faster than SELECT <colname> with large offset
In-Reply-To: <10064.1412303977@sss.pgh.pa.us>
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