Re: Hash index todo list item

On Mon, Sep 03, 2007 at 05:20:34PM -0700, Ben Tilly wrote:
>
> That raises a very random thought. One of the nicer features of
> Oracle is the ability to have function-based indexes. So you could
> index, say, trim(lower(person.name)). There are a *lot* of practical
> situations where that comes in handy. The best workaround that I can
> think of for not having that is to have a column defined to hold the
> result of the function, maintain that column with a trigger, then
> index that column. Which works, but is inelegant. (It also requires
> storing completely redundant data.)
>
> Is there any prospect of postgres aquiring that functionality?
>
> Ben
>
I believe that PostgreSQL already supports functional indexes. In fact,
one suggestion to address the egregiously poor performance of the current
hash index was to replace it with a functional index.

Regards,
Ken