Re: Opinons/Philosophy on adding flags to table to reduce queries?

Would bitmap index lead to anything but 80% pass. I do think, that's far to little selectivity to use an index.

Niall Litchfield <n-litchfield_at_audit-commission.gov.uk> schrieb in im Newsbeitrag: 3b419c55$0$8510$ed9e5944_at_reading.news.pipex.net...
> If the data is fixed would a bitmap index suffice?
>
>
> --
> Niall Litchfield
> Oracle DBA
> Audit Commission UK
> "Jeff Wilson" <jwilson2000_at_home.com> wrote in message
> news:Xgc07.288435$p33.5772965_at_news1.sttls1.wa.home.com...
> > What is the conventional wisdom regarding adding a boolean column to a
 table
> > that is simply the result of a test on the values in about 6 other
 columns?
> >
> > I'm dealing with large tables and my query currently involves conditions
 on
> > the values of these 6 columns. I index all of these columns, but it
 seems
> > like it would be much faster to simply look at a single boolean value.
> > Probably about 80% of the rows in the table pass the boolean test.
> >
> > The data in this table is fixed so I don't have to worry about an update
> > affecting theboolean.
> >
> > Would only a purist avoid something like this? Are there considerations
> > here I'm missing?
> >
> > Thanks.
> >
> > --
> > Jeff Wilson
> > jwilson2000_at_home.com
> > Eugene, Oregon
> >
> > (541) 684-8590
> >
> >
>
>
>
>
Received on Tue Jul 03 2001 - 10:32:41 CDT