Re: What is table "dual"

One reason for Dual is that SQL syntax for SELECT ... requires a FROM

"Jim Kennedy" <kennedy-family_at_home.com> wrote in message news:6xUM7.85560$XJ4.46828397_at_news1.sttln1.wa.home.com...
> It is a special table. It is just a dummy table. You don't add rows to
> this table or delete rows you just select from it. It is so you can do
> evaluations in sql.
> Since you can't say sysdate as a command you might say
> select sysdate from dual;
> Oracle recognizes that you just want the evaluation of the sysdate command
> and so it returns the current date/time.
> you can also say:
> select floor(4,5) from dual;
> and it will evaluate the function floor with the arguments 4 and 5.
> Jim
> "Stjepan Brbot" <Stjepan.Brbot_at_ZG.HiNet.HR> wrote in message
> news:9u10fp$4tv5$1_at_as201.hinet.hr...
> > How to know what one can find in this table (like "sysdate")? Desc on
> > this table does not work!
> >
> > --
> >
> > Stjepan Brbot <Stjepan.Brbot_at_ZG.HiNet.HR>
> >
> >
> > "Jim Kennedy" <kennedy-family_at_home.com> wrote in message
> > news:d3AM7.81442$XJ4.44274249_at_news1.sttln1.wa.home.com...
> > > It is a dummy table that people use for a variety of purposes. e.g.
> > > evaluation
> > >
> > > select sysdate into myVariable from dual;
> > >
> > > Jim
> > >
> > > "Stjepan Brbot" <Stjepan.Brbot_at_ZG.HiNet.HR> wrote in message
> > > news:9tuf3j$1ph9$3_at_as201.hinet.hr...
> > > > See subject ... what is table "dual"?
> > > >
> > > > --
> > > >
> > > > Stjepan Brbot <Stjepan.Brbot_at_ZG.HiNet.HR>
> >
> >
>
> Received on Wed Nov 28 2001 - 06:57:55 CET