Re: Query not using index for user defined type - Mailing list pgsql-hackers

From Rodrigo Barboza
Subject Re: Query not using index for user defined type
Date
Msg-id CANs8QJZnyjnKwvnRKXQuA51ESO50r2G6xnk8mZ2aba1_9ewyiQ@mail.gmail.com
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In response to Re: Query not using index for user defined type  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
<div dir="ltr"><br /><div class="gmail_extra"><br /><br /><div class="gmail_quote">On Mon, Apr 15, 2013 at 7:51 PM, Tom
Lane<span dir="ltr"><<a href="mailto:tgl@sss.pgh.pa.us" target="_blank">tgl@sss.pgh.pa.us</a>></span> wrote:<br
/><blockquoteclass="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div
class="im">RodrigoBarboza <<a href="mailto:rodrigombufrj@gmail.com">rodrigombufrj@gmail.com</a>> writes:<br />
>I created a implic cast for mytype to bigint.<br /> > So when I do the same query it does seq scan, because the
columnis<br /> > transformed into bigint.<br /><br /></div>Yeah.  One reason why there's not an unsigned int type
alreadyis that<br /> it seems impossible to shoehorn it into the numeric promotion hierarchy<br /> without breaking a
lotof existing cases.  You definitely aren't likely<br /> to get nice results by just adding some implicit casts
withoutdoing a<br /> very careful design beforehand.<br /><br />                         regards, tom lane<br
/></blockquote></div><br/></div><div class="gmail_extra" style="style">I just added implicit cast from my type to int8,
numericand float.</div><div class="gmail_extra" style="style">No implicit cast for lower level types.</div><div
class="gmail_extra"style="style"> Isn't it safe?</div><div class="gmail_extra" style="style">The problem would be only
aboutthe index?</div></div> 

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