node.js和MySQL使用Sequelize

node.js和MySQL使用Sequelize

Sequelize 其实就是node.j和MySQL之间的一个桥梁，是用javascript写的object关系映射库。
1. 首先安装依赖：

npm install mysql
npm install sequelize

— Setting up the connection with mysql
2.连接MySQL

//Including dependency
var Sequelize = require("sequelize");
//Setting up the config
var sequelize = new Sequelize('your-database-name', 'db-username', 'db-password', {
    host: "localhost",
    port: 3306,
    dialect: 'mysql'
});

检查连接的状态

sequelize.authenticate().complete(function (err) {
 if (err) { console.log('There is connection in ERROR'); } else { console.log('Connection has been established successfully'); }
});

3.用node.js 创建一个表

//创建表的结构
var Item = sequelize.define('Item', {
    id: Sequelize.STRING,
    name:Sequelize.STRING,
    description: Sequelize.STRING,
    qty: Sequelize.INTEGER
});
//申请项目表数据库
sequelize.sync({force:true}).complete(function (err) {
 if(err){
    console.log('An error occur while creating table');
 }else{
    console.log('Item table created successfully');
 }
});

对数据表的操作

1.插入操作
有两种方法，第一种：

var item1 = Item.build({
    id: 1,
    name:'Laptop',
    description: 'Acer 2340TL',
    qty: 23
});
//Inserting Data into database
item1.save().complete(function (err) {
 if (err) {
    console.log('Error in Inserting Record');
 } else {
    console.log('Data successfully inserted');
 }
});

第二种

sequelize.sync().success(function () {
  Item.create({
     id: 2,
     name:'Cell Phone',
     description: 'Sony',
     qty: 20
  }).success(function (data) {
  console.log(data.values)
 })
});

2.从表中读取数据

//读取所有的数据
Item.find({}).complete(function (err,data) {
    console.log(data);
});
//条件读取
    Item.find({where:{name:'Laptop'}}).complete(function (err, data) {
   console.log(data);
});

3.更新数据表

//更新Laptop 到 Computer
Item.find({where:{name:'Laptop'}}).complete(function (err, data) {
  if(err){
    console.log(err);
  }
  if(data){
    data.updateAttributes({
    name:'Computer'
  }).success(function (data1) {
    console.log(data1);
  })
 }
});

4.从表中删除数据

//删除所有名字为compter的数据
Item.find({where: {name: 'Computer'}}).complete(function (err, data) {
   if (err) {
      console.log(err);
   } else {
      data.destroy({}).success(function (err, data) {
   if(err){
      console.log(err);
   }else{
      console.log(data);
   }
  })
 }
 console.log(data);
});

你可以在 GITHUB上点击查看源代码，也可以查看sequelise官方文档