sequelize

npm install mysql2 sequelize npm install --save-dev sequelize-cli

npx sequelize-cli init

{ "development": { "username": "root", "password": null, "database": "database_dev", "host": "127.0.0.1", "port": 3306, // 값 설정하지 않으면 3306번이 default "dialect": "mysql" }, "test": { "username": "root", "password": null, "database": "database_test", "host": "127.0.0.1", "port": 3306, // default "dialect": "mysql" }, "production": { "username": "root", "password": null, "database": "database_production", "host": "127.0.0.1", "port": 3306, // default "dialect": "mysql" } }

module.exports = function(sequelize, DataTypes) { let user = sequelize.define('User', { id: { type: DataTypes.INTEGER, allowNull: false, }, name: { type: DataString.STRING } }, { timestamps: true }) }

npx sequelize-cli model:generate --name <name> --attributes <field1>:<datatype>,<field2>:<datatype> # attribute 옵션 뒤에 필드와 데이터타입들을 띄어쓰기하면 오류남. 띄어쓰기 사용하려면 ''로 묶어서 사용 #example npm sequelize-cli model:generate --name User --attributes

'use strict'; const { Model } = require('sequelize'); module.exports = (sequelize, DataTypes) => { class Users extends Model { /** * Helper method for defining associations. * This method is not a part of Sequelize lifecycle. * The `models/index` file will call this method automatically. */ static associate(models) { // 모델간의 관계 설정 // define association here } }; Users.init({ id: DataTypes.INTEGER, name: DataTypes.STRING }, { sequelize, modelName: 'user', }); return user; };

'use strict'; module.exports = { up: async (queryInterface, Sequelize) => { await queryInterface.createTable('users', { id: { allowNull: false, autoIncrement: true, primaryKey: true, type: Sequelize.INTEGER }, ... }); }, down: async (queryInterface, Sequelize) => { await queryInterface.dropTable('~'); } };

npx sequelize-cli db:migrate

# 가장 최근의 migration 실행 취소 npx sequelize-cli db:migrate:undo # 모든 migration 실행 취소 npx sequelize-cli db:migrate:undo:all # 특정 migration으로 되돌리기 npx sequelize-cli db:migrate:undo:all --to XXXXXXXXXXXXXX-create-posts.js

npx sequelize-cli migration:generate --name add-column

'use strict'; module.exports = { up: (queryInterface, Sequelize) => { return queryInterface .addColumn( 'ChattingRooms', // name of Target model 'userId2', // name of the key we're adding { type: Sequelize.INTEGER, // setting foreign key relationship references: { model: 'Users', // name of Source model key: 'id', }, // setting when primary key is updated or deleted onUpdate: 'CASCADE', onDelete: 'CASCADE', } ) .then(() => queryInterface.addColumn( 'Users', // name of Target model 'img', // name of the key we're adding { type: Sequelize.STRING, defaultValue: 'https://placeimg.com/140/140/any', } ) ); }, down: (queryInterface, Sequelize) => { return queryInterface .removeColumn( 'ChattingRooms', // name of the Target model 'userId2' // key we want to remove ) .then(() => queryInterface.removeColumn( 'Users', // name of the Target model 'img' // key we want to remove ) ); }, };

npx sequelize-cli seed:generate --name <name>

npx sequelize-cli db:seed:all

# 가장 최근 시드 취소 npx sequelize-cli db:seed:undo # 특정 시드 취소 npx sequelize-cli db:seed:undo --seed name-of-seed-as-in-data # 모든 시드 취소 npx sequelize-cli db:seed:undo:all

user.findOne({ where: { id: userId } })

test.findAll({ attributes: ['id', 'name'] });

const [result, created] = await urlModel.findOrCreate({ where: { url로 데이터 베이스에 찾고 url: url }, defaults: { defaults 옵션으로 없는 경우 기본값으로 새로운 인스터스를 생성할때 title column 을 생성 title: title } }); if(!created) { res.status(201).json(result) } //공식문서에 있는 findOrCreate 예제 코드 const [user, created] = await User.findOrCreate({ where: { username: 'sdepold' }, defaults: { job: 'Technical Lead JavaScript' } }); console.log(user.username); // 'sdepold' console.log(user.job); // This may or may not be 'Technical Lead JavaScript' console.log(created); // The boolean indicating whether this instance was just created if (created) { 부울값으로 반환하는 부분(이미 존재하는지 여부 체크) console.log(user.job); // This will certainly be 'Technical Lead JavaScript' }

// Option 1 Foo.hasOne(Bar, { foreignKey: 'myFooId' }); Bar.belongsTo(Foo); // Option 2 Foo.hasOne(Bar, { foreignKey: { name: 'myFooId' } }); Bar.belongsTo(Foo); // Option 3 Foo.hasOne(Bar); Bar.belongsTo(Foo, { foreignKey: 'myFooId' }); // Option 4 Foo.hasOne(Bar); Bar.belongsTo(Foo, { foreignKey: { name: 'myFooId' } });