Nikhil,
This email will be significantly shorter than the one I wrote 5
minutes ago before my laptop ran out of battery and failed to get
sent.  I didn't explain this clearly so I am going to give an example
(a much smaller one than the one I jsut wrote).
Lets say I have 3 object As (a1, a2, a3) and 3 object Bs (b1, b2, b3).
the relations are as follows:
a1 to (b1, b2), a2 to (b2, b3), a3 to (b1, b3)
The user who makes the request is b2. b2 has a "friend connection"
with b1 only (so b2 to (b1,)).  It could have more friends, but for
simplicity it will have only 1.  What I want to return is this:
a1 to (b1,), a2 to None, a3 to (b1,).

I always want to return all of my model "A" objects, but I want to
filter the model "B" objects within each based on who the current
user's "friend connections are".  How do I do this in code?

On Jun 23, 9:02 pm, Nikhil Somaru <nsom...@gmail.com> wrote:
> Hi Tony,
>
> Try this:
>
> q1 = A.objects.filter(B=your_b1_instance) # that gets you all A with B =
> your_b1_instance
> q2 = A.objects.filter(B__B=your_b2_instance) #that gets you all A with B.B =
> your_b2_instance
> result = set(q1).intersection(set(q2)) #gives you the A's that are common to
> both sets.
> result = list(result) #convert it back to a list
>
> There might be an easier way to do it with just the ORM, but that should
> work for now
>
>
>
>
>
>
>
>
>
> On Thu, Jun 23, 2011 at 8:46 PM, Tony <tonyl7...@gmail.com> wrote:
> > You have the question I was asking correct, your notation was fine.
> > The only thing I should add is I want to return all A, but filter  my
> > "B1"s (as you put it) for each A. I will post my models if need be,
> > but they are on another computer and its not convenient right now.  In
> > the meantime, do you have any ideas for this query?
>
> > On Jun 23, 11:50 am, Nikhil Somaru <nsom...@gmail.com> wrote:
> > > It is very hard to read your message. Please format it appropriately next
> > > time. Avoid repeating variable names and mixing classes with instances.
> > > Could you post your models here?
>
> > > Are you defining the following structure:
>
> > > A hasMany B;
> > > B hasMany A;
> > > B hasMany B;
>
> > > So you want* A such that A.yourB1.yourB2 exists*? Sorry for the notation.
>
> > > On Thu, Jun 23, 2011 at 12:03 PM, Tony <tonyl7...@gmail.com> wrote:
> > > > I have two models with a manytomany through relation (A and B).  B has
> > > > a self referential manytomany relation (a userprofile model).  How
> > > > could I filter objects of model B per each relationship with model A?
> > > > So lets say 3 arbitrary model A objects have 20 model B object
> > > > relations each.  I want to filter the relations so when I return the
> > > > filtered version of model A is outputted, each object of type model A
> > > > returns only object Bs (the userprofiles) that are connected through
> > > > the self referential manytomany relationship to the userprofile (the
> > > > object B, sorry if I use them interchangeably but they are the same
> > > > thing) that is currently sending in the request.  I figure out which
> > > > userprofile is sending the request with a unique identifier sent by
> > > > the user in the request (basically their primary key).  Is this type
> > > > of filtering possible.
>
> > > > --
> > > > You received this message because you are subscribed to the Google
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> > > > "Django users" group.
> > > > To post to this group, send email to django-users@googlegroups.com.
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>
> > > --
> > > Yours,
> > > Nikhil Somaru
>
> > --
> > You received this message because you are subscribed to the Google Groups
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>
> --
> Yours,
> Nikhil Somaru

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