On Fri, Feb 15, 2002 at 11:25:40AM -0500,
Wei Weng <wweng(at)kencast(dot)com> wrote:
> I can understand the rationale behind creating index on tables, it
> speeds up the searching.
>
> But what is the rationale behind creating index on a function? how does
> it help with the database performance?
If a where clause includes a function reference, than an index on that
function can speed up finding rows that satisfy the where clause.