Re: [SQLObject] multiple inheritance tree

[Diez B. R. <die...@ar...>]

On Tuesday 05 December 2006 23:05, Oleg Broytmann wrote:
> (Returning to the list...)
>
> On Tue, Dec 05, 2006 at 10:42:41PM +0100, Diez B. Roggisch wrote:
> > Lets consider this hierarchy:
> >
> > class A:
> >    pass
> >
> > class B(A)
> >    pass
> >
> > class C(B)
> >    pass
> >
> > class D(B)
> >    pass
> >
> > class E(A):
> >    pass
> >
> >
> > Now I have a page that shows all A, using
> >
> > A.select([some_filter_criteria])
> >
> > Then the user can then select to  e.g. only show C and E objects.
> >
> > So - what I need is a way to filter for the type of an object. So
> > C.select() and E.select() isn't exactly what I want. Because then I'd
> > have to recombine the results, including application of sorting criteria
> > - instead of a single select that generates sql like this
> >
> > select ... from A, B, C, D, E where [join all tables by ids] and
> > (B.childName =3D 'C' or A.childName =3D 'E')
>
>    Soemthing like this:
>
> A.select(A.q.childName=3D=3D'B' && B.q.childName=3D=3D'C')
> A.select(A.q.childName=3D=3D'B' && B.q.childName=3D=3D'C' && C.q.childNam=
e=3D=3D'D' &&
> D.q.childName=3D=3D'E')

Unfortunately, that is not working for me. Passing C.q.childName will creat=
e a=20
clause that reads a.child_name.

I'm digging into this - but if there is another solution, like creating=20
explicit table aliases to B and joining them with=20

A.id =3D B.id

and then doing

B.child_name =3D 'C'

I'd be very happy.
=2D-=20
>> Diez B. Roggisch
>> Developer

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