const { DataTypes, Model } = require('sequelize') module.exports = (sequelize) => { class BookSeries extends Model { } BookSeries.init({ id: { type: DataTypes.UUID, defaultValue: DataTypes.UUIDV4, primaryKey: true }, sequence: DataTypes.STRING }, { sequelize, modelName: 'BookSeries', timestamps: false }) // Super Many-to-Many // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship const { Book, Series } = sequelize.models Book.belongsToMany(Series, { through: BookSeries }) Series.belongsToMany(Book, { through: BookSeries }) Book.hasMany(BookSeries) BookSeries.belongsTo(Book) Series.hasMany(BookSeries) BookSeries.belongsTo(Series) return BookSeries }