[Rails] Re: Active Record has_one through
Turns out the event table needed to have an artist_id column. I was attempting to use the join table without a reference to the artist table. I dont know if that was the fix, because i also wrote a function in the event model that used the artist_id to return artist data from the database. I did try your suggestion when initially building the classes...but again, without the artist_id in the event table, it failed. class Event < ActiveRecord::Base has_many :city_events, dependent: :destroy validates :EventID, uniqueness: true def artist Artist.find(artist_id) end def city City.find(city_id) end end -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-talk+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-talk@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rubyonrails-talk/1e2f6f614609a96eb1f15c52d26255c7%40ruby-forum.com. For more options, visit https://groups.google.com/d/optout.
[Rails] Re: Active Record has_one through
why dont you just do this class Artist < ActiveRecord::Base has_many :events, dependent: :destroy end class Event < ActiveRecord::Base belongs_to :artist end a = Artist.first a.events which will return a list of events connected to that artist e = Event.first e.artist which will return the artist that is connected to that event. Maybe explain what your user story is to better understand. With what you posted I comprehended the statement above. -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-talk+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-talk@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rubyonrails-talk/8be9ad7fa3b35df3628035d98ecf187b%40ruby-forum.com. For more options, visit https://groups.google.com/d/optout.
[Rails] Re: Active Record has_one through
On Wednesday, 7 October 2015 20:47:54 UTC-4, Ruby-Forum.com User wrote: > > I have two tables in my app which I am attempting to relate through a > join table. The Artist class which uses 'has_many through', works as > expected. However, the Event class using 'has_one through', brings back > nil. > > class Artist < ActiveRecord::Base > has_many :artist_events, dependent: :destroy > has_many :events, through: :artist_events > end > > class Event < ActiveRecord::Base > belongs_to :artist_event has_one :artist, through: :artist_events > Something hasn't been copied correctly here, because this shouldn't work - the `through` refers to an association (artist_events) that doesn't exist on Event. As noted elsewhere, `belongs_to` is likely not the right association to use here; it's expecting an 'artist_event_id' column on the 'events' table. You'll also want to carefully consider if `has_one` is the right association as well. The table structure you've set up (Artist / ArtistEvent / Event) is a classic many-to-many relationship. If an Event can truly only have one artist, this structure is not needed. If an Event can have many artists, than a has_one isn't correct. --Matt Jones -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-talk+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-talk@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rubyonrails-talk/2fa1934c-fe96-42e6-bcb2-fa4575d30f8a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
