'use strict'; module.exports = { up: function (queryInterface, Sequelize) { return queryInterface.changeColumn('users', 'username', { type: Sequelize.STRING, unique: true }) }, down: function (queryInterface, Sequelize) { sequelize.query( 'ALTER TABLE users DROP CONSTRAINT username_unique_idx;' ); queryInterface.removeIndex('Users', 'username_unique_idx'); } };