So, this:
p = Person
.joins('join organization o on o.id = organization_id')
.where('o.id' => 1)
.select('person.*')
.first!
p.name = 'hi!'
p.save!
works as expected, saving the person's name. But, how would I do this:
p.organization.name = 'bye!'
p.save!
I can't figure out the right projection to get the organization fields to map (or if it's possible). I've tried '*' and 'organization.name as "person.organization.name"'.
In order for what you're doing to work, you have to set the autosave option to true in your belongs_to :organization association.
belongs_to :organization, autosave: true
or just call save on the organization
p.organization.name = 'Org Name'
p.organization.save
You have to declare association in your Person class, using belongs_to has_one has_many has_many :through has_one :through or has_and_belongs_to_many, and Rails will do the join by it self and link your both class together.
Let me paste here a section of Rails guide:
With Active Record associations, we can [..] tell Rails that there is a connection between the two models. Here’s the revised code for setting up customers and orders:
class Customer < ActiveRecord::Base
has_many :orders, :dependent => :destroy
end
class Order < ActiveRecord::Base
belongs_to :customer
end
With this change, creating a new order for a particular customer is easier:
@order = @customer.orders.create(:order_date => Time.now)
I suggest you read the complete guide here: http://guides.rubyonrails.org/association_basics.html
