Re: Relational Algebra Dilemma - Urgent.

"Troy Meyerink" <meyerink_at_usgs.gov> wrote in message news:GvuoAr.4CH_at_igsrsparc2.er.usgs.gov...
> In relational algebra, a where some values exists looks like a
backwards E.
> Im not sure if thats what you want. (I dont have that character on
my font
> list).

I think that's different eh? I think he's _might_ be looking for something like this:

    R2 = select(R1,P)

    Select(Fuzzy,Hairball=Yes)

>
>
>
> "Sted Alana" <Sted_Alana_at_hotmail.com> wrote in message
> news:3cda1610_1_at_news.iprimus.com.au...
> > Hi,
> >
> > Im trying to convert an SQL query into relational form, but I am
stuck
> when
> > trying to write WHERE EXISTS in relational.
> >
> > I know that 'WHERE NOT EXISTS' is simply written as a minus sign
(-).
> >
> > Any help appreciated.
> >
Received on Thu May 09 2002 - 14:51:02 CDT