Expansion of models

Sequelize Models are ES6 classes. You can very easily add custom instance or class level methods.

class User extends Model {
  // Adding a class level method
  static classLevelMethod() {
    return 'foo';
  }
  // Adding an instance level method
  instanceLevelMethod() {
    return 'bar';
  }
}
User.init({ firstname: Sequelize.STRING }, { sequelize });

Of course you can also access the instance's data and generate virtual getters:

class User extends Model {
  getFullname() {
    return [this.firstname, this.lastname].join(' ');
  }
}
User.init({ firstname: Sequelize.STRING, lastname: Sequelize.STRING }, { sequelize });
// Example:
User.build({ firstname: 'foo', lastname: 'bar' }).getFullname() // 'foo bar'

Indexes

Sequelize supports adding indexes to the model definition which will be created during Model.sync() or sequelize.sync.

class User extends Model {}
User.init({}, {
  indexes: [
    // Create a unique index on email
    {
      unique: true,
      fields: ['email']
    },
    // Creates a gin index on data with the jsonb_path_ops operator
    {
      fields: ['data'],
      using: 'gin',
      operator: 'jsonb_path_ops'
    },
    // By default index name will be [table]_[fields]
    // Creates a multi column partial index
    {
      name: 'public_by_author',
      fields: ['author', 'status'],
      where: {
        status: 'public'
      }
    },
    // A BTREE index with an ordered field
    {
      name: 'title_index',
      using: 'BTREE',
      fields: ['author', {attribute: 'title', collate: 'en_US', order: 'DESC', length: 5}]
    }
  ],
  sequelize
});