On Mon, 18 Jan 2010 08:59:56 +1100,
Chris <dmagick@gmail.com> wrote:
>> o Should all foreign keys have an index?
> Not necessarily, you might just want the db to enforce the restriction
> but not actually use the data in it. For example, keep a userid (and
> timestamp) column of the last person to update a row. You may need it
> to say "aha - this was last changed on this date and by person X", but
> you'll never generally use it.
> If you never have a where clause with that column, no need to index
> it. If you're using it in a join all the time, then yes it would be
> better to index it.
Thanks for all your pointers!
Do views use the indexes in the underlying tables, whenever say a SELECT
operation is called on the view? If so, indexes on views don't make any
sense right?
--
Seb
