Rails - Oct 2009 - has_and_belongs_to_many on different databases

Hi, I''m working with two models that have a
"has_and_belongs_to_many"
relation.  Both models reside on a database that it is not the default
one.

A < External
  has_and_belongs_to_many: B

B < External
  has_and_belongs_to_many: A

Retriving the information for A works perfectly, but when trying to
"create" an element on A:

"A.B.create(...)"

ActiveRecord tries to create it on the default database. The solution
was doing:

b = B.find(...)
A.B << b


But, looking on the sourcecode I''ve found on the ActiveRecord file
"has_and_belongs_to_many_association.rb [25:29]"

      def has_primary_key?
        return @has_primary_key unless @has_primary_key.nil?
        @has_primary_key (ActiveRecord::Base.connection.supports_primary_key?
&&
          ActiveRecord::Base.connection.primary_key(@reflection.options
[:join_table]))
      end

Shouln''t it be something like?

      def has_primary_key?
        return @has_primary_key unless @has_primary_key.nil?
        @has_primary_key = (@owner.connection.supports_primary_key? &&
          @owner.connection.primary_key(@reflection.options
[:join_table]))
      end

Thank you

On Oct 16, 10:29 am, erzapito
<erzap...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> Hi, I''m working with two models that have a
"has_and_belongs_to_many"
> relation.  Both models reside on a database that it is not the default
> one.
>
Have you tried using has many through ? with has many through the join
table is also a rails model, so you have a place to say that the join
table should be in this other database.


Fred
> A < External
>   has_and_belongs_to_many: B
>
> B < External
>   has_and_belongs_to_many: A
>
> Retriving the information for A works perfectly, but when trying to
> "create" an element on A:
>
> "A.B.create(...)"
>
> ActiveRecord tries to create it on the default database. The solution
> was doing:
>
> b = B.find(...)
> A.B << b
>
> But, looking on the sourcecode I''ve found on the ActiveRecord file
> "has_and_belongs_to_many_association.rb [25:29]"
>
>       def has_primary_key?
>         return @has_primary_key unless @has_primary_key.nil?
>         @has_primary_key >
(ActiveRecord::Base.connection.supports_primary_key? &&
>           ActiveRecord::Base.connection.primary_key(@reflection.options
> [:join_table]))
>       end
>
> Shouln''t it be something like?
>
>       def has_primary_key?
>         return @has_primary_key unless @has_primary_key.nil?
>         @has_primary_key = (@owner.connection.supports_primary_key?
&&
>           @owner.connection.primary_key(@reflection.options
> [:join_table]))
>       end
>
> Thank you

On Fri, Oct 16, 2009 at 12:31 PM, Frederick Cheung <
frederick.cheung-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> Have you tried using has many through ? with has many through the join
> table is also a rails model, so you have a place to say that the join
> table should be in this other database.

I tried it, but doing some tests I found that it allowed to have more than
one relation between two elements, a new problem that I don''t know how
to
solve.

The real problem was with the library file, deleting elements also fails
because it tries to use the base connection instead of the ancestor''s
one.

-- 
erzapito-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org   @  google talk :D

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Alexandre Paz Mena wrote:
> On Fri, Oct 16, 2009 at 12:31 PM, Frederick Cheung <
> frederick.cheung-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> 
>>
>> Have you tried using has many through ? with has many through the join
>> table is also a rails model, so you have a place to say that the join
>> table should be in this other database.
> 
> 
> I tried it, but doing some tests I found that it allowed to have more 
> than
> one relation between two elements, a new problem that I don''t know
how
> to
> solve.
validates_uniqueness_of and a unique index in the DB.  Done.

Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen-sbuyVjPbboAdnm+yROfE0A@public.gmane.org
-- 
Posted via http://www.ruby-forum.com/.