"Michael" <dayzman@hotmail.com> wrote in message
news:48e30213.0406152231.6e19331c@posting.google.com...
> Hi,
> If I have R(a integer PRIMARY KEY, b text, c text, d integer); and I
> want to find how many different entries there are, (specified using b
> and c instead of a), is "select count(distinct b||c) from R" an
> appropriate query?
Try:
select count(1) from
(select distinct b, c from R);
However, your prof may not like this answer.