Nope - 2 tanks. Each tank contains a grade of fuel. The tanks table is
linked to the grades table AND to the nozzles table. One tank = 1 Grade,
but 1 tank can have many nozzles. Each nozzle must have one and only one tank.

At 12:08 AM 23/07/2003 +1000, Helen Borrie wrote:

>At 03:54 PM 22/07/2003 +0200, you wrote:
> >Hi all,
> >
> >when I execute the following SQL, I get duplicates records. Anyone know why?
> >
> >There are 2 nozzles and 2 grades of fuel.
> >
> >SELECT T.Grade, G.Descrip,
> >N.LSold as VolSold, N.MSold as MoneySold
> >FROM Tanks T JOIN Nozzles N
> >on
> >T.Number = N.Tank
> >JOIN
> >Grades G
> >ON
> >T.Grade = G.Grade_Num
> >Order by T.Grade, G.Descrip
>
>There are 4 tanks?
>
>heLen
>
>
>
>
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