From: Josh Berkus <josh@agliodbs.com>
To: PostgreSQL Server <postgres@rsd.it>
To: pgsql-sql@postgresql.org
Subject: Re: INDEX PROBLEMS ?
Date: Sat, 16 Nov 2002 11:06:20 -0800
Message-ID: <web-1829092@davinci.ethosmedia.com> (raw)
In-Reply-To: <Pine.LNX.4.44.0211161901570.8254-100000@sunrise2.radiostudiodelta.it>
Alex,
> On postgres 7.2.3 I have found what follows:
>
> explain select * from documents where iddoc>1;
>
> Seq Scan on lotti (cost=0.00..831.79 rows=26783 width=98)
>
> EXPLAIN
> explain select * from documents where iddoc=1;
>
> Index Scan using lotti_pkey on lotti (cost=0.00..2.26 rows=1
> width=98)
>
> Why index is not used for operators > and < ????
Because ">" is returning 26,000 rows. When you return that many rows,
a Seq Scan is faster.
-Josh
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To: pgsql-sql@postgresql.org
Cc: josh@agliodbs.com, postgres@rsd.it
Subject: Re: INDEX PROBLEMS ?
In-Reply-To: <web-1829092@davinci.ethosmedia.com>
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