Rails - Dec 2005 - Using :include "recursively" (including the children of the child)?

Hi,

Let''s say I have the following hierarchy of tables:

Group <- parent
Location <- child of Group
School <- child of Location
Phone <- child of School

Then, if I want to do this:

Location.find(...someparms..., :include => [:schools, :group, :phones])

I get an association error (Association was not found). I guess it 
happens because AR is looking in the Location model for the Phones 
association, which only exists in the School model (I also tried 
singular, :phone).

Is there any way I can load all Phone records at once? I wouldn''t mind 
using custom SQL if that''s the only solution.

Thanks in advance!

Ivan V.

PS: Merrrrry christmas!

On Fri, Dec 16, 2005 at 02:14:57PM -0600, Iv?n Vega Rivera
wrote:
> Is there any way I can load all Phone records at once? I wouldn''t
mind
> using custom SQL if that''s the only solution.
There is no way to do that using the eager loading implementation. It would
require custom SQL.

marcel
-- 
Marcel Molina Jr. <marcel-WRrfy3IlpWYdnm+yROfE0A@public.gmane.org>

Marcel Molina Jr. wrote:
> On Fri, Dec 16, 2005 at 02:14:57PM -0600, Iv?n Vega Rivera wrote:
>   
>> Is there any way I can load all Phone records at once? I
wouldn''t mind
>> using custom SQL if that''s the only solution.
>>     
>
> There is no way to do that using the eager loading implementation. It would
> require custom SQL.
>
> marcel
>   
Would it be possible to load the phones for the object:

@locs = Location.find(...someparms..., :include => [:schools, :group])

and then something like:

@locs.schools.phones.load_all (of course this method doesn''t exist, but
is there something similar?)

Or could I "find" all the phones that belong to certain schools and
then
assign those to the specific @locs.schools object?

Thanks!

Ivan V.

If it''s just for the location, then you could include a redundant
foreign
key (has_many) to the phones.  Then you could use Location.find(
...someparams :include => [:phones])

Alternativley a method in the Locations model could look something like for
the current location

def self.get_phones
  Phone.find_by_sql(
       "SELECT phones.* FROM phones p, locations l, schools s
        WHERE l.id = #{id} AND s.location_id = l.id AND p.school_id =
s.id")
end

In which case you could use @some_location.get_phones

going a bit further than that it might be possible to use something like

@phone_numbers = Location.find( :all ).collect {  |loc|
       loc.get_phones}
@phone_numbers.flatten!


I haven''t tested andy of this tho....  Hope it works :)

On 12/16/05, Iván Vega Rivera
<ivanvega-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
>
> Marcel Molina Jr. wrote:
> > On Fri, Dec 16, 2005 at 02:14:57PM -0600, Iv?n Vega Rivera wrote:
> >
> >> Is there any way I can load all Phone records at once? I
wouldn''t mind
> >> using custom SQL if that''s the only solution.
> >>
> >
> > There is no way to do that using the eager loading implementation. It
> would
> > require custom SQL.
> >
> > marcel
> >
> Would it be possible to load the phones for the object:
>
> @locs = Location.find(...someparms..., :include => [:schools, :group])
>
> and then something like:
>
> @locs.schools.phones.load_all (of course this method doesn''t
exist, but
> is there something similar?)
>
> Or could I "find" all the phones that belong to certain schools
and then
> assign those to the specific @locs.schools object?
>
> Thanks!
>
> Ivan V.
>
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> Rails mailing list
> Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org
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>

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