Re: Need help with cost based optimizer "logic"

"DA Morgan" <damorgan_at_x.washington.edu> a écrit dans le message de news:1113321096.673173_at_yasure...
> Syltrem wrote:
>
> > "Kevin Crosbie" <caoimhinocrosbai_at_yahoo.com> a écrit dans le message de
> > news:1113317629.6036914f3560cecbc6980b78fcdc04a3_at_teranews...
> >
> >>Try a functional index:
> >
> >
> > I could, but still I would like to understand what the optimizer is
doing
>
> Then run a 10053 trace but I doubt you'll learn anything other than the
> fact that you could have saved a lot of time building a FUNCTION BASED
> index.
> --

I did the 10053 trace and I asked a specific question about the results (see original post)

I'm currently working on the application side to try and prevent it from using UPPER().
As a last resort I wll create a function based index on the column, but as it is all uppercase in the database anyway, that seems dumb.

Users say it was faster last week but my time machine is currently out of order so I can't know for sure. It doesn't make any sense that it could be faster then as the same plan gets generated with last week's stats and the table is 99% the same data.

-- 
Syltrem

http://pages.infinit.net/syltrem (OpenVMS related web site, en français)


> Daniel A. Morgan

> University of Washington

> damorgan_at_x.washington.edu

> (replace 'x' with 'u' to respond)