From: Bruno Wolff III <bruno@wolff.to>
To: Ying Lu <ying_lu@cs.concordia.ca>
Cc: pgsql-sql@postgresql.org
Subject: Re: Index creation question for expression (col1 || '-' || col2)
Date: Fri, 8 Jul 2005 11:57:14 -0500
Message-ID: <20050708165714.GA9501@wolff.to> (raw)
In-Reply-To: <42CEA509.3090507@cs.concordia.ca>
References: <42CEA509.3090507@cs.concordia.ca>
On Fri, Jul 08, 2005 at 12:08:41 -0400,
Ying Lu <ying_lu@cs.concordia.ca> wrote:
> Greetings,
>
> A question about creating index for the following expression.
>
> CREATE INDEX idx_t1 ON test (col1 || '-' || col2);
>
> May I know is it possible and how I may create index for the expression
> such as "col1 || '-' || col2" for a table please?
You have already received some answers to this specific question.
However, you might consider a different solution to the underlying
problem. You can make a multicolumn index that for many purposes would
be better than the above functional index.
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To: pgsql-sql@postgresql.org
Cc: bruno@wolff.to, ying_lu@cs.concordia.ca
Subject: Re: Index creation question for expression (col1 || '-' || col2)
In-Reply-To: <20050708165714.GA9501@wolff.to>
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