Double belongs to in AR?

Rails
1

Can you do a double belongs to in ActiveRecord? I wanted a column
made up of user ids matched with group ids (since I can’t think of a
better way with my current knowledge of AR).

Something like the following:

class User<ActiveRecord::Base
has_many user_groups
end

class Group<ActiveRecord::Base
end

class UserGroup<ActiveRecord::Base
belongs_to :user
belongs_to :group
end

#how would you make that work?

Thanks,
Kyle

2

You are very very close:

class User<ActiveRecord::Base
has_many :user_groups
has_many :groups, :through=>:users
end

class Group<ActiveRecord::Base
has_many :user_groups
has_many :users, :through=> :user_groups
end

class UserGroup<ActiveRecord::Base
belongs_to :user
belongs_to :group
end

Might I suggest a name change? UserGroup might work better as
Membership.
It reads better, and it represents the actual entity you’re trying to
handle. You can then use that model to manage the relationships
directly.
Find that record, delete it, and a user is no longer a member of a
group.

group = Group.find(15)
group.memberships.create :user=>User.find(1) #add to a group
Membership.create(:user_id=>2, :group_id=>15) #another way to add to a
group
Membership.find_by_user_id_and_group_id(1,15).destroy #delete a user
from
a group

Hope that helps!