class CreateExerciseUserQuestions < ActiveRecord::Migration[5.2] def change create_table :exercise_user_questions do |t| t.integer :exercise_id, index: true t.integer :exercise_user_id, index: true t.integer :user_id, index: true t.integer :exercise_question_id, index: true t.timestamps end add_index :exercise_user_questions, [:exercise_user_id, :exercise_question_id], name: "index_on_user_question", unique: true end end