Sequelize增刪改查與事務 | Sequelize

Sequelize ORM

1.數據的增刪改查與事務

初始化模型

const { Sequelize, Model, DataTypes } = require("sequelize");


const sequelize = new Sequelize({
    dialect: "mysql",
    host: "localhost",
    port: 3306,
    username: "root",
    password: "password",
    database: "demo",
    timezone: "+08:00",
    pool: {
        max: 10,
        min: 0
    },
    logging: true,
});


class User extends Model {}

User.init({
    id: {
        type: DataTypes.INTEGER({ unsigned: true }),
        primaryKey: true,
        autoIncrement: true,
        comment: "用戶ID",
    },
    username: {
        type: DataTypes.STRING(40),
        unique: true,
        allowNull: false,
        comment: "賬號",
    },
    password: {
        type: DataTypes.CHAR(64),
        allowNull: false,
        comment: "密碼",
    },
}, {
    sequelize: sequelize,
    tableName: "user",
    modelName: "user",
    paranoid: true,  // 邏輯刪除，填充刪除時間
    underscored: true,  // 內置字段用下划線代替駝峰命名
});

• 增

  • 單條插入

    (async ()=>{
        try{
            await sequelize.sync({force: true});
            const user = await User.create({
                username: "mkl",
                password: "123456",
            });
            console.log("創建成功", user.toJSON());
        } catch(e){
            console.log(e);
        }
    })();
    

  • 批量插入

    (async ()=>{
        try{
            await sequelize.sync({force: true});
            const users = await User.bulkCreate([
                {username: "mkl", password: "123456"}, 
                {username: "bob", password: "123456"},
            ], {
                individualHooks: true, // 對每個數據都執行一次生命周期，為false只執行bulkCreate的生命周期
            });
            console.log("創建成功", users.map(user=>user.toJSON()));
        } catch(e){
            console.log(e);
        }
    })();
    

• 更新

  • 批量更新

    (async ()=>{
        try{
            // await sequelize.sync({force: true});
            const [count, users] = await User.update({username: "bob", password: "123456"},
            {
                where: {
                    username: 'marry',
                },
                individualHooks: true, // 對每個數據都執行一次生命周期，為false只執行bulkCreate的生命周期
            });
            console.log(`總共更新了${count}`, users.map(user=>user.toJSON()));
        } catch(e){
            console.log(e);
        }
    })();
    

  • 單條更新

    (async ()=>{
        try{
            const user = await User.findOne({
                where: {
                    username: "bob"
                }
            });
            if (!user){
                throw new Error("用戶不存在.");
            }
            user.password = "password";
            await user.save();
            console.log(user.toJSON());
        } catch(e){
            console.log(e);
        }
    })();
    

• 刪除

  • 批量刪除(邏輯)

    (async ()=>{
        try{
            const count = await User.destroy({
                where: {
                    username: "bob"
                }
            });
            console.log(`刪除了${count}條數據.`)
        } catch(e){
            console.log(e);
        }
    })();
    

  • 單條刪除(物理)

• 查詢

  • 單條查詢

    根據ID查詢

    (async ()=>{
        /**
        * 根據ID查詢
        */
        const userById = await User.findByPk(1);
        console.log(userById?userById.toJSON():"未查到數據");
    })();
    

    findOne根據where查詢

    (async ()=>{
        /**
        * 根據條件查詢，並返回指定字段
        */
        const user = await User.findOne({
            attributes: ["password"],
            where: {
                username: "mkl",
            }
        });
        console.log(user?user.toJSON():"未查到數據");
    })();
    

  • 多條查詢

    (async ()=>{
        /**
        * 根據條件查詢，並返回指定字段
        */
        const user = await User.findAll({
            attributes: ["password"],
            where: {
                username: "mkl",
            },
            order: [
                ["id", "DESC"],
                ["username", "DESC"],
            ],
            offset: 0,
            limit: 10
        });
        console.log(user);
    })();
    

  • 查詢或創建單條數據

    (async ()=>{
        /**
        * 根據條件查詢，並返回指定字段
        */
        const [user, created] = await User.findOrCreate({
            where: {
                username: "bob",
            },
            defaults: {
                username: "bob",
                password: "password",
            }
        });
        if (created){
            console.log("創建用戶成功", user.toJSON());
        } else {
            console.log("查詢用戶成功", user.toJSON());
        }
        console.log(user);
    })();
    

  • 同時查詢列表和數據總數

    (async ()=>{
        const {rows, count} = await User.findAndCountAll({
            where: {
                username: "mkl",
            }
        });
        console.log(rows.map(row=>row.toJSON()), count);
    })();
    

  • 統計數據

    (async () => {
        const count = await User.count({
            where: {
                username: "mkl",
            }
        });
        console.log(count);
    })();
    

  • 運算符

    查看上一篇博客

• 事務

  • 自動事務

    (async () => {
        const result = await sequelize.transaction({
            isolationLevel: Transaction.ISOLATION_LEVELS.SERIALIZABLE  // 設置隔離級別
        }, async (transaction) => {
            const user = await User.create({
                username: "marry",
                password: 123,
            }, {transaction: transaction});  // 選項中必須傳遞事務對象
            const user2 = await User.create({
                username: "jerry",
                password: 456,
            }, {transaction: transaction});
            return [user, user2];
        });
        console.log(result.map(user=>user.toJSON()));
    })();
    

  • 手動事務

    (async () => {
        const transaction = await sequelize.transaction({
            isolationLevel: Transaction.ISOLATION_LEVELS.SERIALIZABLE,
        });
        try{
            const user = await User.create({
                username: "miaokela",
                password: "password",
            }, {transaction: transaction});
            const user2 = await User.create({
                username: "boby",
                password: "123456",
            });
            await transaction.commit();
        } catch(e){
            await transaction.rollback();
            throw e;
        }
    })();