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Message-ID: <4FF68B2B.50505@ringerc.id.au>
Date: Fri, 06 Jul 2012 14:52:27 +0800
From: Craig Ringer <ringerc@ringerc.id.au>
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To: Pavel Stehule <pavel.stehule@gmail.com>
CC: CSS <css@morefoo.com>, pgsql-performance@postgresql.org
Subject: Re: select operations that generate disk writes
References: <C6B622D6-5DE1-48FB-BF8B-2C8065FEA346@morefoo.com>
	<CAFj8pRDijqBPdGen1BggTfnNzpfNHLo=t6n1gRZoiiB6o4J7kQ@mail.gmail.com>
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On 07/06/2012 02:20 PM, Pavel Stehule wrote:
> Hello
>
> 2012/7/6 CSS <css@morefoo.com>:
>> So my question is, what else can generate writes when doing read-only operations?  I know it sounds like a simple question, but I'm just not finding a concise answer anywhere.
> statistics http://www.postgresql.org/docs/9.1/interactive/runtime-config-statistics.html
>

  Hint bits, too:

http://wiki.postgresql.org/wiki/Hint_Bits

--
Craig Ringer

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    <div class="moz-cite-prefix">On 07/06/2012 02:20 PM, Pavel Stehule
      wrote:<br>
    </div>
    <blockquote
cite="mid:CAFj8pRDijqBPdGen1BggTfnNzpfNHLo=t6n1gRZoiiB6o4J7kQ@mail.gmail.com"
      type="cite">
      <pre wrap="">Hello

2012/7/6 CSS <a class="moz-txt-link-rfc2396E" href="mailto:css@morefoo.com">&lt;css@morefoo.com&gt;</a>:
</pre>
      <blockquote type="cite">
        <pre wrap="">
So my question is, what else can generate writes when doing read-only operations?  I know it sounds like a simple question, but I'm just not finding a concise answer anywhere.
</pre>
      </blockquote>
      <pre wrap="">
statistics <a class="moz-txt-link-freetext" href="http://www.postgresql.org/docs/9.1/interactive/runtime-config-statistics.html">http://www.postgresql.org/docs/9.1/interactive/runtime-config-statistics.html</a>

</pre>
    </blockquote>
    <br>
     Hint bits, too:<br>
    <br>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8">
    <a href="http://wiki.postgresql.org/wiki/Hint_Bits">http://wiki.postgresql.org/wiki/Hint_Bits</a><br>
    <br>
    --<br>
    Craig Ringer<br>
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