Date: Wed, 6 Feb 2002 10:50:20 +0100
From: Isabelle Brette <isabelle@apartia.fr>
To: Chris Ruprecht <chrup999@yahoo.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: indexes
Message-ID: <20020206095020.GA1124@aparima.com>
Reply-To: isabelle@apartia.fr
References: <20020205170524.GA1990@aparima.com>
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Hi again,

On Tue, Feb 05, 2002 at 11:50:52AM -0600, Chris Ruprecht wrote:
> Isabella,

Mh, it's Isabelle, thanks.

> I would do a
> create index sess_created on sessions (ip, to_char);
> 
> This satisfies the where clause and might help in the group by.

This does not seem to work.

One thing or two I did not say in my previous post :

- the 'created' column is a timestamp, so the to_char function needs a
  second argument to know which format to use.
  
- the 'ip' column is of postgres type inet, that's why I use the <<
  operator.

- for some other queries, I also need a filter on IPs but not on the
  timestamp.

For the ip thing, I just looked at the doc and it seems a '<<' operator
on inet columns just can't use an indexed column properly. All I can do
is simple comparisons such as <, <=, =, >=, > (only the btree access
method is implemented in my current version of Postgres : 7.1.3 ; will
this change in 7.2 ?).

-- 
Isabelle Brette - isabelle@apartia.fr