Re: Sequence Scan vs. Index scan

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
>
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