From: Reimer <carlosreimer@terra.com.br>
To: Fernando Lujan <fernando.lujan@mandic.com.br>
To: pgsql-performance@postgresql.org
Subject: Re: Sequence Scan vs. Index scan
Date: Tue, 21 Mar 2006 15:23:08 -0300
Message-ID: <001a01c64d14$80f4a840$8b00000a@reimer> (raw)
References: <44204107.3040708@mandic.com.br>
Fernando,
If you need to read all the table for example it would be better to read
only the data pages instead of read data and index pages.
Reimer
----- Original Message -----
From: "Fernando Lujan" <fernando.lujan@mandic.com.br>
To: <pgsql-performance@postgresql.org>
Sent: Tuesday, March 21, 2006 3:08 PM
Subject: [PERFORM] Sequence Scan vs. Index scan
> Hi guys,
>
> I'm trying to figure out when Sequence Scan is better than Index Scan. I
> just want to know this because I disabled the sequence scan in postgresql
> and receive a better result. :)
>
> Two tables.
>
> Table 1 (1 million rows )
> -----------
> id
> text
> table2_id
>
> Table 2 (300 thousand rows)
> ----------
> id
> text 2
>
> When I join these two tables I have a sequence_scan. :(
>
> Thanks in advance.
>
> Fernando Lujan
>
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend
>
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To: pgsql-performance@postgresql.org
Cc: carlosreimer@terra.com.br, fernando.lujan@mandic.com.br
Subject: Re: Sequence Scan vs. Index scan
In-Reply-To: <001a01c64d14$80f4a840$8b00000a@reimer>
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