similar to: Nuby Question: How best to read a child record?

Hi there I need to store additional attributes on join table. Searching the Wiki [1] revealed two possible methods: 1) push_with_attributes, as described by Justin Palmer [2]. Unfortunately, "this method is now deprecated" [3]. Even if it wasn''t, there seem to be inherent problems with that approach, for example with updating those additional attributes, though Joshua Muheim

I wonder if you can have more than one has_many :through association between 2 models. For example... I have a model Teacher and a model Class Now, 1 Teacher works in many Classes, right?. So I need a join model like class Work < ActiveRecord::Base belongs_to :teacher belongs_to :class end But I also would like to know if a teacher CAN teach a class before I

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...

All, I''m building model objects for existing tables that I cannot modify. In AWDWR, Dave says "Note that our join table has no id column...The second reason for not including an id column in the join table is that AR automatically includes all columns from the join tables when accessing rows using it. If the join table included a column called id, its id would overwrite the id

Hello, I have the usual Categories and Products table scenario, mediated by a Categories_Products join table. When I create a new Product and into a given Category, I notice that my join table is not being populated. Shouldn''t the join Categories_Products table be populated? Thanks, gk -- Posted via http://www.ruby-forum.com/.

I have the following two tables: create table teams ( id int not null auto_increment, short_name varchar(12) not null, long_name varchar(50) not null, logo varchar(20) not null, primary key (id) ); create table rounds ( id int not null auto_increment, home_team_id int not null, away_team_id int

Hi, I''ve been googling and searching the forums for some time but can''t seem to find exactly what I''m looking for. Suppose User HABTM Products (for example a favorites list). I would like to construct a single query for finding Products ordered by the number of Users that have flagged them as favorites. Although I can construct the query using SQL a with a

If I have belongs_to :user Do I need to have validates_presence_of :user_id ? Does Rails validate the presence of :user_id automatically if I have belongs_to :user? In other words, does Rails prevent against creating orphan records that belong to non-existent users? Thanks. -- Posted via http://www.ruby-forum.com/.

Hi, Day 3 with rails here. Forgive me. If this has been covered many times before, pls just point me at the article. I worked through the Rolling with Rails tutorial (http://www.onlamp.com/pub/a/onlamp/2005/01/20/rails.html) built up my cookbook. Things work great. I now want to add Ingredients to my app. So, a Recipe will have 1 or more Ingredients and any single ingredient can be

I just took my HABTM and turned it into a :through since my join table has another "non-joiny" attribute. I went from this: has_many_and_belongs_to :jobs, :join_table => ''tablename'', :foreign_key => ''x'', :association_foreign_key => ''y'' to this: has_many :jobs, :through =>

Hi I have a has_many :through. It''s a basic mapping of Project id .... User id .... TeamMembers project_id user_id role What I would like to do is have different roles so I can have in the project model has_many :core_members, :through => :team_members, :source => :user but I would like to limit this to only those with the "core" role in the team members table for

I have this code that is using svn externals with rails EDGE working fine for the past couple of months. A couple of days ago, this code died. Even after deleting vendor/rails, this code doesnt work: class Tag < ActiveRecord::Base has_many :taggings has_many :events, :through => :taggings has_many :users, :through => :taggings end class User < ActiveRecord::Base # Virtual

It seems that using a join model that joins with two has_many''s will fail to generate proper SQL class StudentSemesterRecord < ActiveRecord::Base belongs_to :semester has_many :discipline_records, :through => :semester end class Semester < ActiveRecord::Base has_many :student_semester_records has_many :discipline_records end class DisciplineRecord <

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

I am using many-to-many using :through since I need to store additional information in the join table. I am doing this and it seems to work. I want to verify that this is the best way to do this. Tables foods - id, food foodallergies - food_id, symptom_id, a few other columns symptoms - id, symptom Models class Food < ActiveRecord::Base has_many :foodallergies has_many :symptoms,

Hi, How do I associate two different tables which have a lookup id (table) as common. I tried the has_many :table2, :through => look_up_table in my table1 model. Any hints? Thanks, Hari -- Posted via http://www.ruby-forum.com/.

I''d like to use :through to create a web of associations like: class Thing < ActiveRecord::Base has_many :child_things, :through => :thing_thing has_many :parent_things, :through => :thing_thing, :some_other_option? end class ThingThing < ActiveRecord::Base belongs_to :thing belongs_to :child_thing, :class_name => ''Thing'', :foreign_key =>

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

Hi, I have a self-referential has_many :through relationship setup to track relationships between users. Basically relationships are modeled as a join table with an extra column ''relation''. create table relationships ( user_id integer unsigned not null, friend_id integer unsigned not null, relation char(1) not null, ) --- relations --- f = friend r = request to

A concrete example: We''re building a system to organize the information about workshops being held in various conventions. A convention has more than one workshop, and each workshop can be held in more than one convention. Also each workshop has a host, who is specific to a workshop being held in a specific convention. For example, Matz may host an "Introduction to Ruby"