Re: Cube Index Size

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От Heikki Linnakangas
Тема Re: Cube Index Size
Дата
Msg-id 4DE62485.9080904@enterprisedb.com
обсуждение исходный текст
Ответ на Cube Index Size  (Nick Raj <nickrajjain@gmail.com>)
Ответы Re: Cube Index Size  (Alexander Korotkov <aekorotkov@gmail.com>)
Re: Cube Index Size  (Teodor Sigaev <teodor@sigaev.ru>)
Список pgsql-hackers
On 01.06.2011 10:48, Nick Raj wrote:
> On Tue, May 31, 2011 at 12:46 PM, Heikki Linnakangas<
> heikki.linnakangas@enterprisedb.com>  wrote:
>> If not, please post a self-contained test case to create and populate the
>> table, so that others can easily try to reproduce it.
>>
>
>    I have attached .sql file that having 20000 tuples
>    Table creation - create table cubtest(c cube);
>    Index creation - create index t on cubtest using gist(c);

Ok, I can reproduce the issue with that. The index is only 4MB in size 
when I populate it with random data (vs. 15 MB with your data). The 
command I used is:

INSERT INTO cubtest SELECT cube(random(), random()) FROM 
generate_series(1,20000);

My guess is that the picksplit algorithm performs poorly with that data. 
Unfortunately, I have no idea how to improve that.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


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