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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
In-reply-to: 
 <CAN1FPGN1ynBj3m1DMszc9MEYVj41S96OMy8-Q1cgKMGxv482SA@mail.gmail.com>
References: 
 <CAN1FPGN1ynBj3m1DMszc9MEYVj41S96OMy8-Q1cgKMGxv482SA@mail.gmail.com>
Comments: In-reply-to Marc Slemko <marcs@znep.com>
 message dated "Thu, 02 Oct 2014 19:17:48 -0700"
Date: Thu, 02 Oct 2014 22:39:37 -0400
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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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