class CreateDoctrineSubjects < ActiveRecord::Migration[6.1]
  def change
    create_table :doctrine_subjects do |t|
      t.references :doctrine, null: false
      t.references :subject, null: false
      t.integer    :rank, null: false, default: 1

      t.timestamps
    end

    add_index :doctrine_subjects, %i[doctrine_id subject_id], unique: true
  end
end