Horton

Re: [PATCHES] Multi-column GIN

Oleg Bartunov <oleg@sai.msu.su>

View thread View on postgr.es
From: Oleg Bartunov <oleg@sai.msu.su>
To: Teodor Sigaev <teodor@sigaev.ru>
Cc: Heikki Linnakangas <heikki@enterprisedb.com>, Patches <pgsql-patches@postgresql.org>, Pgsql Hackers <pgsql-hackers@postgresql.org>
Date: 2008-07-04T09:13:17Z
Lists: pgsql-hackers 
On Fri, 4 Jul 2008, Teodor Sigaev wrote:

>> What's the benefit of a multi-column GIN index over multiple
>> single-column GIN indexes?
>
> Page 12 from presentation on PgCon 
> (http://www.sigaev.ru/gin/fastinsert_and_multicolumn_GIN.pdf):
>
> Multicolumn index vs.  2 single column indexes
>
> Size:    539 Mb        538 Mb
> Speed:   *1.885* ms    4.994 ms
> Index:   ~340 s        ~200 s
> Insert:  72 s/10000    66 s/10000

Well, another reason is a index feature-completeness

 	Regards,
 		Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83