associations

I have the model Member that contains all informations about the registered member on my site. Then I have the model Message which contains 2 columns (actually 3 with id ): - member_id - message_from In the table Messages are stored IDs of user, how chatting together - when the member A send message to member B , so in the column member_id is saved ID of person A and into the column message_from ID of the person B . My current associations looks like: class Member < ActiveRecord::Base has_many :messages_from end class Message < ActiveRecord::Base belongs_to :member end I don't know, how could

I followed the steps from here to setup a favorites relationship between a user model and a company model. Specifically, a user can have many favorite companies. There is also a functionality of a user being tied to a company on creation. So here are my current models/routes/db schema Models class FavoriteCompany < ActiveRecord::Base belongs_to :company belongs_to :user ... class User < ActiveRecord::Base has_many :companies has_many :favorite_companies has_many :favorites, through: :favorite_companies ... class Company < ActiveRecord::Base belongs_to :user has_many :favorite_companies has

In my application, I have to models: Workflow and Step; steps belongs_to workflow and a workflow has_many steps. Steps have an index and a boolean status ('completed'). I want to retrieve workflows whose step 1 is completed and step 2 is not, i.e. something like this in SQL: SELECT * FROM workflows w INNER JOIN steps s1 ON s1.workflow_id = w.id INNER JOIN steps s2 ON s2.workflow_id = w.id WHERE s1.index = 1 AND s1.completed = 1 AND s2.index = 2 AND s2.completed = 0 I've tried to express this query with Squeel, but it seems it does not allow multiple joins on the same association: I cannot find

In a Rails app, I'm using FactoryGirl to define a general factory plus several more specific traits. The general case and all but one of the traits have a particular association, but I'd like to define a trait where that association is not created/built. I can use an after callback to set the association's id to nil , but this doesn't stop the association record from being created in the first place. Is there a way in a trait definition to completely disable the creation/building of an association that has been defined for the factory the trait belongs to? For example: FactoryGirl.define do

I have associated a file extension with my Delphi 2009 program. I have been using the command line call method to pass the filename to my Delphi program so it can be opened. However, I found that when selecting multiple files, and clicking on them all at once, it opens each file in a separate instance of my program. I asked about this , and apparently the solution is to use one of the other two Windows methods: DDE or IDropTarget . But DDE is being deprecated, and MSDN recommends the IDropTarget method. Also Lars Truijens in his answer to me , says that IDropTarget might fit better if I'm