Re: MV Keys
Date: Wed, 8 Mar 2006 12:46:51 +0200
Message-ID: <dumcmt$pk4$1_at_emma.aioe.org>
"Marshall Spight" <marshall.spight_at_gmail.com> wrote in message
news:1141786943.958538.182130_at_i40g2000cwc.googlegroups.com...
> David Cressey wrote:
> > [a bunch of good stuff.]
>
> Yes.
>
> Nothing in the RM says an equality test will execute within some
> specific performance deadline. You can join on two long
> blob columns and the equality test will be a binary compare,
> which is O(n); it could be a long wait. Joining two RVA
> attributes that lack an index will likely be as you describe:
> requiring a sort and therefore O(n logn). (With an index
> we can do much better.)
The complexity of a problem is a budget you can spend by buying space and/or
time.
The problems are minimizing the error and balancing.
Received on Wed Mar 08 2006 - 11:46:51 CET