Re: One question about transformation ANY Sublinks into joins - Mailing list pgsql-hackers

From Dilip Kumar
Subject Re: One question about transformation ANY Sublinks into joins
Date
Msg-id CAFiTN-u92gq_cXCCsbSw8oGYyd0T6T=N70fVmAG8w3g_9N1LVw@mail.gmail.com
Whole thread Raw
In response to Re: One question about transformation ANY Sublinks into joins  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
<div dir="ltr"><div class="gmail_extra"><br /><div class="gmail_quote">On Thu, Jul 21, 2016 at 9:53 PM, Robert Haas
<spandir="ltr"><<a href="mailto:robertmhaas@gmail.com" target="_blank">robertmhaas@gmail.com</a>></span>
wrote:<br/><blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">Itwould need
tobe a Hash Semi Join rather than a Hash Join, wouldn't it?</blockquote></div><br />I guess, Hash Join will do
here, </div><divclass="gmail_extra">because inner hash node is, on hash aggregate with group key on <span
style="font-size:12.8px">t2.id2,t2.c2</span></div><div class="gmail_extra"><span style="font-size:12.8px">and hash join
conditionis </span><span style="font-size:12.8px">(t1.id1 = t2.id2) AND (t1.c1 = t2.c2).</span></div><div
class="gmail_extra"><spanstyle="font-size:12.8px"><br /></span></div><div class="gmail_extra"><span
style="font-size:12.8px">SoI think these together will make sure that we don't get duplicate tuple for one outer
record.</span></div><divclass="gmail_extra"><br /></div><div class="gmail_extra">-- <br /><div class="gmail_signature"
data-smartmail="gmail_signature"><divdir="ltr"><span style="color:rgb(80,0,80);font-size:12.8px">Regards,</span><br
style="color:rgb(80,0,80);font-size:12.8px"/><span style="color:rgb(80,0,80);font-size:12.8px">Dilip Kumar</span><br
style="color:rgb(80,0,80);font-size:12.8px"/><span style="color:rgb(80,0,80);font-size:12.8px">EnterpriseDB: </span><a
href="http://www.enterprisedb.com/"style="color:rgb(17,85,204);font-size:12.8px"
target="_blank">http://www.enterprisedb.com</a><br/></div></div></div></div> 

pgsql-hackers by date:

Previous
From: David Steele
Date:
Subject: Re: Password identifiers, protocol aging and SCRAM protocol
Next
From: Tom Lane
Date:
Subject: Re: Password identifiers, protocol aging and SCRAM protocol