From: | Gaetano Mendola <mendola(at)bigfoot(dot)com> |
---|---|
To: | Rhaoni Chiu Pereira <rhaoni(at)sistemica(dot)info>, "pgsql-admin(at)postgresql(dot)org" <pgsql-admin(at)postgresql(dot)org> |
Subject: | Re: How can I make PosgreSQL use an Index ? |
Date: | 2003-09-17 21:54:34 |
Message-ID: | 3F68D81A.2030801@bigfoot.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-admin |
Rhaoni Chiu Pereira wrote:
> Hi list,
>
> I have a table like this:
>
> CREATE TABLE "gsames00" (
> "ano_mes" varchar(6) NOT NULL,
> "descricao" varchar(30),
> PRIMARY KEY ("ano_mes")
> );
>
> and an index like this:
>
> CREATE INDEX GSAMES01 ON GSAMES00 (ANO_MES);
>
> When I run a explain analyze with this where clause:
>
> ... gsames00.ano_mes = to_char(ftnfco00.data_emissao,'YYYYMM') AND ...
>
> ftnfco00.data_emissao is a timestamp. When I run the explain analyze it says:
>
> ...
> -> Seq Scan on gsames00 (cost=100000000.00..100000006.72 rows=372 width=10)
> (actual time=0.01..0.96 rows=372 loops=19923)
> ...
looking at the cost I guess that you never run vacuum analyze on your
table, do it and let us know.
Regards
Gaetano Mendola
From | Date | Subject | |
---|---|---|---|
Next Message | Rhaoni Chiu Pereira | 2003-09-17 21:54:38 | Re: How can I make PosgreSQL use an Index ? |
Previous Message | Dirk Lutzebaeck | 2003-09-17 21:32:21 | huge pg_toast_<OID>_index files? |