similar to: has_and_belongs_to_many find with multiple predicates?

I''ve got a fixed list of several thousand Things, and a User base that may grow to who knows how big (we can only hope ,right?) Users have and belong to many Things. I want to display a list of top Things, based on how many users each has. Things with 0 users are not displayed. Two questions. First, I expect the density of the relatioships to focus on a small percentage of the

Hi there, I''ve got a table construction like this: presentation contactstate Hilton new Mc Donalds emailed etc. called visited etc. Now i''ve created an join table presentationcontactstate with extra fields like comment and date time. so i know for example when i called a specific presentation. Now

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

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

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 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 am having some trouble figuring out how to model self-referential entities in Rails. I have a "group" model, which can have 0 or more "group" objects or 0 or more "user" objects. I tried creating a subgroup table that has a parent_group_id and a child_group_id as foreign keys but can''t figure out how to create the mapping in my ruby model

I''m having a problem with a has_and_belongs_to_many (habtm) association between two models with extra attributes. I''m writing a comic book database, and each issue has many creators on it. Thing is, some creators perform multiple duties. They may write one issue, draw another, etc. However, if I add a creator twice to an issue and try to delete it, it removes both creators:

hey, i my database i have users and groups, each user can get in different groups my db structure: table groups: id, name, basegroup, firm_id table users: id, firstname, lastname, email table groups_users: group_id, user_id my relation is a many to many: class Group < ActiveRecord::Base has_and_belongs_to_many :users end class User < ActiveRecord::Base has_and_belongs_to_many

I know there have been threads on this before but I was thinking shouldn''t multiple collection_select automatically update habtm relations when you update_attributes? In order to get multiple collection_select to work I use: collection_select(:user, :group_ids, Group.find(:all), :id, :name,{},{:multiple=>'''',:name=>''group[id][]''}) In fact if 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...

Hello List, I''m a bit spent on this problem, and my code might be whack. I seem to be encountering a problem where the primary key on a join table is not being resolved correctly. I will elaborate after some code bits. I am creating the join table using migrations, and relevant model code is this: class Post < ActiveRecord::Base has_and_belongs_to_many :records

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

I didn''t find exactly an answer on this one, so I''d like to get a clarification from folks who live & breathe HABTM. class foo has_and_belongs_to_many :bars end class bar has_and_belongs_to_many :foos end (and yes, I have a bars_foos table in my db) def test_habtm bar = Bar.new foo = Foo.new foo.bars<<bar assert !foo.bars.empty? assert

Hi, I know that this goes against MVC, but is there any way to render a partial from a model? The reason for me wanting to do this is that the caching logic is quite complex and I would like to keep it in the model. Thanks, GiantCranes -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the

Taking time off from programming is always painful :-). I have the following Models: ==== class Tag < ActiveRecord::Base has_and_belongs_to_many :problems end class Problem < ActiveRecord::Base belongs_to :user has_and_belongs_to_many :tags end ==== And the following migrations: ==== create_table "problems" do |t| t.column "user_id", :integer

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"

hey, i my database i have users and groups, each user can get in different groups my db structure: table groups: id, name, basegroup, firm_id table users: id, firstname, lastname, email table groups_users: group_id, users_id my relation is a many to many: class Group < ActiveRecord::Base has_and_belongs_to_many :users end class User < ActiveRecord::Base has_and_belongs_to_many

If I have a class, Asset, which has and belongs to many associated Asset objects, how do I do this? has_and_belongs_to_many :associated_assets, :class => "Asset", :foreign_key => ?????, :association_foreign_key => ????? Right now, my table has a :first_asset_id and a :second_asset_id, but I don''t see how the objects themselves are supposed to distinguish one from 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