similar to: DB Modelling the Rails way - Opinions??

Hi, I''m somewhat of a Rails newbie and am trying to understand how to formulate n-way (3 or 4 way) joins in Rails (where the join tables contain extra data as well.) Let me give you my basic entities: foos id - pk name - unique bars id - pk name - unique bazs id - pk name - unique frozs id - pk name - unique then i have two separate join tables: foos_bars_bazs - 3 way join

Chris, Finally got time to fully play with your suggestions. Had to re-code a bit of stuff but the concept works - just like a bought one :~). Many thanks for the solution, Kind Regards, Eric. For those curious - here''s what it was about; On Monday 02 January 2006 02:10, Eric Sloane tried to type something like: > Hi, > I''m trying to figure the most efficient way to

Hi Chris, Yesterday you kindly submitted an answer to my question on modelling many to many relationships. I''ve briefly tried the proposed solution but so far with no luck. Before I get too involved - I''d like to know if mapping three way :join_tables is "legal" in a Rails sense. I only ask since you put (untested) in your mail and I can''t find any docs on

Hello All, I am new to ROR, and can''t seem to get HABTM to cooperate entirely... however I might be abusing it! Before I try a different strategy I thought I''d ask here and see if I''m missing something simple. So say Projects and Companies are related. Projects can have multiple Companies, and Companies can be on multiple Projects. But, the same Company can also

Hello everyone, first post to the list and a relative newbie to Rails development. Done quite a bit of JSP, PHP, HTML, XML etc and thought I would kick the tires on Rails to see if it can speed up development for internal applications. Anyway, I am running into a problem that is just driving me crazy and everything I read on the net doesn''t seem to help. I was hoping someone here might

Heyo! I am setting up a self-referencial habtm relationship with the users of my app. I am using Chad Fowler''s "Rails Recipes" to get me started, and everything works great with the join table "people_friends". I add friends by doing somebody.friends << somebodyelse. However, with my app, there is an approval process so my join table has columns person_id,

Hi, I have 3 tables with HABTM relation. USERS -> QUOTE_TO_USER <- QUOTES Table QUOTE_TO_USER has 3 attributes: quote_id, user_id, component. I have a form where I can tie multiple users to QUOTE. This is easy one, thru "user_ids" (@quote[:user_ids] = @params[:quote][:user_ids]). In this form I have all users and I just check those I want to tie to this quote, however

Hi all I have the following models: class member has_and_belongs_to_many :disc_jockeys end class disc_jockey has_and_belongs_to_many :members end The relation table is called disc_jockeys_members and has the following fields: disc_jockeys_members(disc_jockey_id, member_id, status) So far, the field status can have values like valid, invalid, locked etc., but it is not regarded yet by

Imagine I want to track people, and the clubs that they belong to. table people with columns person_id, person_name table clubs with columns club_id, club_name And I have the association table: table clubs_people with columns person_id, club_id Now I know how to do this habtm between the two, in order to associate people with clubs that they belong to. However my application also needs a

For a while, I''ve been getting that HMT is replacing HABTM. It appears that HMT can do all of what HABTM can do and more. The question is: Should I stop using HABTM? Let''s take a simple case: A case has many categories For a given category, there are certain valid statuses Category has_and_belongs_to_many :statuses Status has_and_belongs_to_many :categories Question: Is

I read somewhere that the correct naming of bridge tables is in alpha order. For example. I have two tables: houses, and colors. If I want to create a bridge table to associate colors with houses, I would name the table: colors_houses The associations work fine. But, if I have a table named: track_houses. Building a bridge table called: colors_track_houses, gives me model associaton errors.

Hello all This is my first post so excuse the basic question. (and any repeats I just got an email saying this post was too big so I have re-submitted a smaller version) I was following the thread on http://lists.rubyonrails.org/pipermail/rails/2006-May/038988.html regarding the STI on HABTM for RoR. I have a very similar problem and was hoping for some help. I have the

Greetings railsers - I''m trying to add to a collection through HABTM, but the sql insert is trying to insert a PK rather than letting mysql produce the auto_increment''ed PK. ## @medication_dose holds a validated, saved model @medication_dose.medication_frequencies << MedicationFrequency.find (:all) The above bails with, Mysql::Error: #23000Duplicate

So having just learned how to do has_many :through as opposed to HABTM, and then, being concerned that I wouldn''t get it to work, I started thinking about these two approaches. It seems to me that the _only_ problem that the HM:T (has_many :through) approach solves that HABTM doesn''t is the issue of the potential collision of id columns between your join table and one of

Is it me or is my model getting the created_at from the wrong model! I have a HABTM relationship between Problems and Tags. In one of my controller I do the following: def view @tag = Tag.find_by_name @params[:id] end In my view I do this: <% @tag.problems.each do |problem| %> ... <%= problem.created_at %> ... <% end %> Now, how come the created_at

Class Role has_and_belongs_to_many :users Class User has_and_belongs_to_many :roles Class RolesUsers has_and_belongs_to_many :roles has_and_belongs_to_many :users According to the logs...I''m good through here @roles_users = RolesUsers.find(:all, :conditions => ["user_id = ?", params[:users_id]] ) the next section of controller code is a problem...

Hi, I''m having a little trouble figuring out how to make a self- referential HABTM bi-directional. I have a Employee class. Each employee can have a couple of bosses, who are also employees. The employee class has the following HABTM: has_and_belongs_to_many :bosses, :class_name => "Employee", :join_table => "bosses_courses", :association_foreign_key =>

I have a problem declaring a relationship through a join_table ; the SQL generated by ActiveRecord is correct, but there are two columns called ''id'', and the final object gets the ''wrong'' column ... Here''s a more detailed description of the data, code, and problem :- There''s a People table, with id, name, and a few things. Also a

Hi all, I''m working with a legacy sqlserver db and I''m trying to override the insert sql in as defined in the HABTM method below(becasue the join has three primary keys), but I''m getting the error: ''undefined local variable or method `record'' for Project:Class'' has_and_belongs_to_many :people, :class => ''Person'',

Hello! I have 2 table: users and buddies User: id, name, ... Buddy: id, user_id, user_buddy_id, ... So if you have 2 users 1,jack and 2,fred and fred is a buddy of jack, there is a Buddy object: id=1, user_id=1, user_buddy_id=2 I can declare only one belongs_to in Buddy and one has_many in User. And there is conflict if I had the second one (the first one is discarded) class User has_many