Skip site navigation (1) Skip section navigation (2)

Re: hash index improving v3

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Alex Hunsaker" <badalex(at)gmail(dot)com>
Cc: "Zdenek Kotala" <Zdenek(dot)Kotala(at)sun(dot)com>, "Xiao Meng" <mx(dot)cogito(at)gmail(dot)com>, pgsql-patches(at)postgresql(dot)org, "Jonah H(dot) Harris" <jonah(dot)harris(at)gmail(dot)com>
Subject: Re: hash index improving v3
Date: 2008-09-05 02:19:05
Message-ID: 12087.1220581145@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-hackerspgsql-patches
"Alex Hunsaker" <badalex(at)gmail(dot)com> writes:
> On Thu, Sep 4, 2008 at 7:13 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> * check that the queries actually use the indexes (not sure that the
>> proposed switch settings ensure this, not to mention you didn't create
>> the indexes)

> Well I was assuming I could just test the speed of a hash join...

Uh, no, hash joins have nearly zip to do with hash indexes.  They rely
on the same per-datatype support functions but that's the end of the
commonality.

			regards, tom lane

In response to

pgsql-hackers by date

Next:From: Brendan JurdDate: 2008-09-05 02:48:43
Subject: Re: Need more reviewers!
Previous:From: Tom LaneDate: 2008-09-05 02:17:07
Subject: Re: hash index improving v3

pgsql-patches by date

Next:From: Alex HunsakerDate: 2008-09-05 03:48:41
Subject: Re: hash index improving v3
Previous:From: Tom LaneDate: 2008-09-05 02:17:07
Subject: Re: hash index improving v3

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group