Rails find over multiple models

Question

I think I'm missing something very obvious and its making my brain hurt.

class User < ActiveRecord::Base
has_one :profile

class Profile < ActiveRecord::Base
has_one :user
belongs_to :team

I have a partial that loops through the users and print some basic info, I'm using this partial in my team show page.

I had originally written this to return users who's profiles were a member of a team.

def show
@team = Team.find_by_id(params[:id])
@profiles= Profile.find(:all, :conditions => ['team_id = ?', @team.id])
@users = User.find_by_id(@profiles.user_id)
end

But quickly realized @profiles was an array, and it looks messy as hell. Stuck as to what my find should look like to select all User who have a profile that is a member of a team.

The partial that is working elsewhere for displaying users looks like this

<% for user in @users%>
<table>
<tr>
        <td>
        <%= image_tag user.profile.picture.url %>
        </td>
        <td>
        <a href="/users/<%= user.id %>"><%= user.login %></a>
        </td>
        <td>
        <%= user.profile.first_name %> <%= user.profile.second_name %>
        </td>
        <td>
        <%= user.profile.status %>
        </td>
</tr>
</table>
<% end %>

Development log output with updated show and relationships

Processing TeamsController#show (for 127.0.0.1 at 2010-03-30 22:06:31) [GET]
  Parameters: {"id"=>"1"}
  User Load (1.3ms)   SELECT * FROM "users" WHERE ("users"."id" = 3) LIMIT 1
  Team Load (1.0ms)   SELECT * FROM "teams" WHERE ("teams"."id" = 1) 
Rendering template within layouts/main
Rendering teams/show
Completed in 75ms (View: 11, DB: 2) | 200 OK [http://localhost/teams/1]

Answer 1

I would change your associations to something like this:

class User < ActiveRecord::Base
has_one :profile

class Profile < ActiveRecord::Base
belongs_to :user
belongs_to :team

class Team < ActiveRecord::Base
has_many :profiles
has_many :users, :through => :profiles

I think the problem you are having is that in a has_one relationship one has to be the owner and one has to be the ownee.. (belongs_to)

Then you should be able to find associations using the following:

@user.profile
@team.users
@team.profiles

etc..

If you want the user to have a profile and the team to display its user's profiles you would change the models to this:

class User < ActiveRecord::Base
has_one :profile
belongs_to :team

class Profile < ActiveRecord::Base
belongs_to :user

class Team < ActiveRecord::Base
has_many :users
has_many :profiles, :through => :users

This way you could load your team, its users and the users profiles:

@team = Team.find(params[:id])
@users = @team.users
@profiles = @team.profiles

Good luck!

In order for your associations to work properly with the above code your db tables will need to have the following:

Your profiles table will need to have user_id as an integer.

Your users table will need to have team_id as an integer.

Your teams table doesn't need any ids.

Verify that your migrations setup these id's properly and that when a user is created that it is associated with your team properly:

@team.users << @user

Hope that helps!

Answer 2

Change your association as follows:

class User < ActiveRecord::Base
  has_one :profile
end

class Profile < ActiveRecord::Base
  belongs_to :user
  belongs_to :team
end

class Team < ActiveRecord::Base
  has_many :profiles
  has_many :users, :through => :profiles
end

Make sure you have user_id and team_id columns on profiles table.

Change your show method as follows:

def show
  @team   = Team.find(params[:id])
  @profile= @team.profile
  @user   = @profile.user
end

PS:

Above code will work if a team has one profile and a profile belongs to a team and a user.