Re: Index creation question for expression (col1 || '-' || col2) - Mailing list pgsql-sql

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.