Ecto.Associations.HasMany.Proxy

A has_many association.

Create

A new struct of the associated model can be created with struct/2. The created struct will have its foreign key set to the primary key of the parent model.

defmodule Post do
  use Ecto.Model

  schema "posts" do
    has_many :comments, Comment
  end
end

post = put_primary_key(%Post{}, 42)
struct(post.comments, []) #=> %Comment{post_id: 42}

Reflection

Any association module will generate the __assoc__ function that can be used for runtime introspection of the association.

• __assoc__(:loaded, assoc) - Returns the loaded entities or :not_loaded;
• __assoc__(:loaded, value, assoc) - Sets the loaded entities;
• __assoc__(:target, assoc) - Returns the model where the association was defined;
• __assoc__(:name, assoc) - Returns the name of the association field on the model;
• __assoc__(:primary_key, assoc) - Returns the primary key (used when creating a model with new/2);
• __assoc__(:primary_key, value, assoc) - Sets the primary key;
• __assoc__(:new, name, target) - Creates a new association with the given name and target;