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Message-ID: <4D7F1F5D.4010709@nsoft.lt>
Date: Tue, 15 Mar 2011 10:12:13 +0200
From: Julius Tuskenis <julius@nsoft.lt>
Organization: UAB nSoft
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To: pgsql-performance@postgresql.org
Subject: Re: unexpected stable function behavior
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Thank you, Tom for you answer

2011.03.14 19:17, Tom Lane rašė:
> That function property*allows*  the optimizer to
> invoke the function fewer times than would happen in an un-optimized
> query.  It does not*require*  it to do so.
Thank you for clearing that for me. I think these 2 sentences in 
documentation 
(http://www.postgresql.org/docs/current/interactive/xfunc-volatility.html) 
would prevent misunderstandings in the future.

-- 
Julius Tuskenis
Programavimo skyriaus vadovas
UAB nSoft
mob. +37068233050


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    Thank you, Tom for you answer<br>
    <br>
    2011.03.14 19:17, Tom Lane rašė:
    <blockquote cite="mid:12872.1300123053@sss.pgh.pa.us" type="cite">
      <pre wrap="">That function property <b class="moz-txt-star"><span class="moz-txt-tag">*</span>allows<span class="moz-txt-tag">*</span></b> the optimizer to
invoke the function fewer times than would happen in an un-optimized
query.  It does not <b class="moz-txt-star"><span class="moz-txt-tag">*</span>require<span class="moz-txt-tag">*</span></b> it to do so.</pre>
    </blockquote>
    Thank you for clearing that for me. I think these 2 sentences in
    documentation (<a
href="http://www.postgresql.org/docs/current/interactive/xfunc-volatility.html">http://www.postgresql.org/docs/current/interactive/xfunc-volatility.html</a>)
    would prevent misunderstandings in the future. <br>
    <br>
    <pre class="moz-signature" cols="72">-- 
Julius Tuskenis
Programavimo skyriaus vadovas
UAB nSoft
mob. +37068233050</pre>
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