Menu
I have a Slot model, belonging to the Configuration model as well as another model:
In db/migrate/...create_slots.rb:
t.references :slottable, :polymorphic => true
In app/models/slot.rb:
belongs_to :slottable, :polymorphic => true
In app/models/configuration.rb:
has_many :slots, :as => :slottable
In rails console I get:
ruby-1.9.2-p180 :009 > Slot.last
=> #<Slot id: 69, slottable_id: 35, slottable_type: "configuration", number: 2, usage: "1GB 667MHz DDR2 SDRAM PC2-5300 SO-DIMM", created_at: "2011-08-09 12:12:25", updated_at: "2011-08-09 12:12:25">
ruby-1.9.2-p180 :009 > Slot.last.slottable
NameError: wrong constant name configuration
The only explanation I can come up with is that I've misunderstood the use of the slottable_type column. Have I?
At present, in app/models/configuration.rb:
slot = Slot.find_or_create_by_slottable_id_and_slottable_type(self.id, "configuration")
203
Polymorphic relationship in Rails refers to a type of Active Record association. This concept is used to attach a model to another model that can be of a different type by only having to define one association.
The basic structure of a polymorphic association (PA)sets up 2 columns in the comment table. (This is different from a typical one-to-many association, where we'd only need one column that references the id's of the model it belongs to). For a PA, the first column we need to create is for the selected model.
The slottable_type has to be Configuration and not configuration.
167
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
