class CreateKnowledgePointContainers < ActiveRecord::Migration[5.2]
  def change
    create_table :knowledge_point_containers do |t|
      t.references :knowledge_point
      t.integer :container_id
      t.string :container_type

      t.timestamps
    end
    add_index :knowledge_point_containers, [:knowledge_point_id, :container_id, :container_type], name: "container_index", unique: true
  end
end