From: Silvio Brandani <silvio.brandani@tech.sdb.it>
To: Szymon Guz <mabewlun@gmail.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: database not using indexes, yet
Date: Fri, 18 Nov 2011 15:41:36 +0100
Message-ID: <4EC66EA0.9020900@tech.sdb.it> (raw)
In-Reply-To: <CAFjNrYvvBgm=qG2cPjqojhJ_pfAMgTT-q1Abq4-R3X4BAtixRQ@mail.gmail.com>
References: <4EBA9AAC.9030900@tech.sdb.it>
<4EC66726.6060800@tech.sdb.it>
<CAFjNrYvvBgm=qG2cPjqojhJ_pfAMgTT-q1Abq4-R3X4BAtixRQ@mail.gmail.com>
table is 959818 records,
I create a copy of the table with create tabase as select ... and
then indexed, the new table use the indexes ...
thanks
Il 18/11/2011 15.19, Szymon Guz ha scritto:
>
>
> 2011/11/18 Silvio Brandani <silvio.brandani@tech.sdb.it
> <mailto:silvio.brandani@tech.sdb.it>>
>
> On postgres 8.3.11 on linux centos 5 we have a table not too big
> with primary key index on
>
> Indexes:
> "aida_references_pkey" PRIMARY KEY, btree (aida_reference_id)
>
> the query not use index:
>
> aidadb=# explain analyze select aida_reference_id from
> aida.aida_references where aida_reference_id = '3145';
> QUERY PLAN
> ----------------------------------------------------------------------------------------------------------------
> Seq Scan on aida_references (cost=0.00..51489.15 rows=1 width=4)
> (actual time=0.173..1457.643 rows=1 loops=1)
> Filter: (aida_reference_id = 3145)
> Total runtime: 1457.696 ms
>
>
> already executed the vacuum ,reindex.
>
> Please help
>
> --
> Silvio Brandani
>
>
>
> Hi Silvio,
> how many rows do you have in the table?
> Usually PostgreSQL doesn't want to use index when the table is small.
>
>
> regards
> Szymon
>
>
> --
> *http://simononsoftware.com/*
>
--
Silvio Brandani
Infrastructure Administrator
SDB Information Technology
Phone: +39.055.3811222
Fax: +39.055.5201119
---
Utilizziamo i dati personali che la riguardano esclusivamente per nostre finalità amministrative e contabili, anche quando li comunichiamo a terzi. Informazioni dettagliate, anche in ordine al Suo diritto di accesso e agli altri Suoi diritti, sono riportate alla pagina http://www.savinodelbene.com/privacy.html
Se avete ricevuto questo messaggio per errore Vi preghiamo di ritornarlo al mittente eliminandolo assieme agli eventuali allegati, ai sensi art. 616 codice penale http://www.savinodelbene.com/privacy/codice_penale_616.html
L'Azienda non si assume alcuna responsabilità giuridica qualora pervengano da questo indirizzo messaggi estranei all'attività lavorativa o contrari a norme.
--
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: silvio.brandani@tech.sdb.it, mabewlun@gmail.com
Subject: Re: database not using indexes, yet
In-Reply-To: <4EC66EA0.9020900@tech.sdb.it>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox