datatypes
url:string
foriegn_keys:references
association
dependent: :destroy
Destroying the children is ideal. You do that by setting dependent: :destroy on the has_many relationship. Like so:class Parent ApplicationRecord has_many :children, dependent: :destroy end
https://blog.getcensus.com/cascading-deletes-in-rails/
bookmark.rb (bookmark model)
validates_uniqueness_of :movie_id, scope: :list_id