Today I Learned

hashrocket A Hashrocket project

Direct many-to-many ActiveRecord associations

By using has_and_belongs_to_many you can directly relate models with a many-to-many-association. For example, if you have a model Film and a model Producer, a film can have multiple :producers, and a Producer can have multiple :films; in this case, each of models could have a has_and_belongs_to_many association with the other.

class Film < ApplicationRecord
  has_and_belongs_to_many :producers

class Producer < ApplicationRecord
  has_and_belongs_to_many :films
#Now associative records can be stored and retrieved
film = Film.where(title: "The Irishman")
producer = Producer.where(name: "Martin Scorcese")
film.producers << producer

#=> This should return a collection including The Irishman
#=> This should return a collection including Martin Scorcese
See More #rails TILs
Looking for help? Hashrocket has been an industry leader in Ruby on Rails since 2008. Rails is a core skill for each developer at Hashrocket, and we'd love to take a look at your project. Contact us and find out how we can help you.