node.js学习笔记(4)_极客学院_MongoDB的使用

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u014267209/article/details/52085138

一.基本使用

1.特点:

    ->使用BSON存储数据
    ->支持相对丰富的查询操作   
    ->支持索引
    ->副本集(活跃节点,备份节点)
    ->分片
    ->无模式
    ->部署简单方便

2.启动命令:

mongod --dbpath=G:\NodeJS\MongoDB\data\db --port=xxxxx
    ->dbpath:指定数据库的路径
    ->默认的端口号是:27017
mongo:mongo数据库的客户端工具
    ->mongo:默认的本机数据库
    ->mongo 127.0.0.1:27017  连接到指定的数据库
    ->show dbs:
    ->user dbname:    e.g:use part9
    ->db.users.insert({"username":"Linyongzhi"}):插入数据
        ==>WriteResult({ "nInserted" : 1 })
    ->db.users.find():查看数据
        ==>{ "_id" : ObjectId("579eeff52a825343289a2f1f"), "username" : "Linyongzhi" }
    ->db.users.find({"username":"Linyongzhi"}):查看数据
        ==>{ "_id" : ObjectId("579eeff52a825343289a2f1f"), "username" : "Linyongzhi" }
    ->db.users.find().count():获取条数
    ->db.users.update({"username":"Linyongzhi"},{$set{"age":18}}),默认只修改第一条
    ->db.users.update({"username":"Linyongzhi"},{$set{"age":18}},{multi:true}):可以修改多条
    ->db.users.save(),也可以进行修改
    ->db.users.remove({"username":"Zhangxiaojin"}):删除所有满足条件的行
    ->db.users.remove({"username":"Zhangxiaojin"},true):删除满足条件的第一行
    ->db.users.remove({}):删除所有的行
    ->db.users.drop():删除所有的行,包括索引  

二.使用Mongose模块操作MongoDB

1.连接数据库兵创建Schema:

var mongoose = require('mongoose')
var uri = 'mongodb://username:password@hostname:port/databasename';
uri = 'mongodb://localhost/part9';

mongoose.connect(uri);

var BookSchema = new mongoose.Schema({
    name: String,
    author: String,
    publishTime : Date
});

mongoose.model('Book',BookSchema);

2.插入数据

var mongoose = require('mongoose')
require('./model.js');

var Book = mongoose.model('Book');

var book = new Book({
    name : "MEAN Web",
    author : "Green",
    publishTime: new Date()
});

    book.author = 'Jim';
    book.save(function(err){
    console.log('sava status:' , err? 'failed' : 'success' );   
});

3.查找数据

var mongoose = require('mongoose')
require('./model.js');

var Book = mongoose.model('Book');

Book.find({},function(err,docs){
    if(err){
        console.log('err',err);
        return;
    }
    console.log('result:'+docs);
})
--------------------------------
//查找一条记录
var mongoose = require('mongoose')
require('./model.js');

var Book = mongoose.model('Book');

Book.findOne({name:"Jim"},function(err,doc){
    if(err){
        console.log('err',err);
        return;
    }
    doc.name = 'Node.js';
    doc.save();
    console.log('result:'+doc);
})

4.删除数据

var mongoose = require('mongoose')
require('./model.js');

var Book = mongoose.model('Book');

Book.findOne({name:"Jim"},function(err,doc){
    if(err){
        console.log('err',err);
        return;
    }
    doc.remove();
    console.log('result:'+doc);
});

5.条件查询

var mongoose = require('mongoose')
require('./model.js');

var Book = mongoose.model('Book');

var cond = {
    $or : [
        {name:'Jim'},
        {name:'Node.js'}
    ]
}

Book.find(cond,function(err,docs){
    if(err){
        console.log('err',err);
        return;
    }

    console.log('cond:',cond,'result:',docs);
})

三.在Express中使用MongoDB

项目的结构:

1.config.js

module.exports = {
    mongodb : "mongodb://localhost/part9"
};

2.mongoose.js

var mongoose = require('mongoose');
var config = require('./config.js');

module.exports = function(){
    var db = mongoose.connect(config.mongodb);
    require('../models/user.server.model.js');
    return db;
}

3.user.server.model.js

var mongoose = require('mongoose');

var UserSchema = new mongoose.Schema({
    uid : Number,
    username : String,
    createTime : Date,
    lastLogin : Date 
});

mongoose.model('User',UserSchema);
}

4.user.js

//...
var mongoose = require('mongoose');
var User = mongoose.model('User');

router.get('/test', function(req, res, next) {
   var user = new User({
        uid : 1,
        username : 'Linyongzhi'
   });
//保存操作
   user.save(function(err){
        if(err){
            res.end('Error');
            return next();
        }

        User.find({},function(err,docs){
            if(err){
                res.end('Error');
                return next();
            }
            res.json(docs);
        });
   });
});