From: | Antony Paul <antonypaul24(at)gmail(dot)com> |
---|---|
To: | pgsql-performance(at)postgresql(dot)org |
Subject: | Re: Index not used with or condition |
Date: | 2005-02-07 11:14:07 |
Message-ID: | 2989532e0502070314402057cc@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-performance |
On more investigation I found that index scan is not used if the query
have a function in it like lower() and an index exist for lower()
column.
rgds
Antony Paul
On Mon, 7 Feb 2005 14:37:15 +0530, Antony Paul <antonypaul24(at)gmail(dot)com> wrote:
> Hi all,
> I am facing a strange problem when I run EXPLAIN against a table
> having more than 100000 records. The query have lot of OR conditions
> and when parts of the query is removed it is using index. To analyse
> it I created a table with a single column, inserted 100000
> records(random number) in it created index and run a query which
> returns 1 record which have no or condition and it was using index. I
> added an OR conditon and is using sequential scan. I set the
> enable_seqscan to off. I ran the tests again and is using index scan.
> So which one I have to use. Is this any bug in Explain.
>
> rgds
> Antony Paul.
>
From | Date | Subject | |
---|---|---|---|
Next Message | Joost Kraaijeveld | 2005-02-07 11:36:24 | Is this possible / slow performance? |
Previous Message | Antony Paul | 2005-02-07 09:07:15 | Index not used with or condition |