Home > Web Front-end > JS Tutorial > nodejs connects to mongodb database to implement addition, deletion, modification and query

nodejs connects to mongodb database to implement addition, deletion, modification and query

高洛峰
Release: 2016-12-03 09:15:36
Original
1361 people have browsed it

Preparation

1. Install mongodb through npm command

2. Install mongodb database

CRUD operation

Before this, you should have some understanding of the MongoDB database and some of its add, delete, check and modify commands.

1. Add

var MongoClient = require("mongodb").MongoClient;
var DB_URL = "mongodb://localhost:27017/chm";
 
function insertData(db)
{
  var devices = db.collection('vip');
  var data = {"name":"node","age":22,"addr":"nb","addTime":new Date()};
  devices.insert(data,function(error, result){
    if(error)
    {
      console.log('Error:'+ error);
    }else{
 
      console.log(result.result.n);
    }
    db.close();
  });
}
 
  
MongoClient.connect(DB_URL, function(error, db){
  console.log('连接成功!');
  insertData(db);
});
Copy after login

2. Find

var mongodb = require('mongodb')
var MongoClient = require('mongodb').MongoClient;
var DB_CONN_STR = 'mongodb://localhost:27017/chm'; 
 
var selectData = function(db, callback) { 
 //连接到表 
 var collection = db.collection('vip');
 //查询数据
 var whereStr = {"name":'node'};
 collection.find(whereStr,function(error, cursor){
  cursor.each(function(error,doc){
    if(doc){
      //console.log(doc);
      if (doc.addTime) {
        console.log("addTime: "+doc.addTime);
      }
    }
  });
 
 });
 
}
 
MongoClient.connect(DB_CONN_STR, function(err, db) {
 console.log("连接成功!");
 selectData(db, function(result) {
  console.log(result);
  db.close();
 });
});
Copy after login

3. Update

var MongoClient = require("mongodb").MongoClient;
var DB_URL = "mongodb://localhost:27017/chm";
 
MongoClient.connect(DB_URL, function(error, db){
  console.log("连接成功!");
  updateData(db);
});
 
function updateData(db)
{
  var devices = db.collection('vip');
  var whereData = {"name":"node"}
  var updateDat = {$set: {"age":26}}; //如果不用$set,替换整条数据
  devices.update(whereData, updateDat, function(error, result){
    if (error) {
      console.log('Error:'+ error);
    }else{
      console.log(result);
    }
    db.close();
  });
}
Copy after login

4. Delete

var MongoClient = require('mongodb').MongoClient;
var DB_URL = "mongodb://localhost:27017/chm";
 
MongoClient.connect(DB_URL, function(error, db){
  console.log("连接成功");
  deleteData(db);
});
 
function deleteData(db)
{
  var devices = db.collection('vip');
  var data = {"name":"node"};
  devices.remove(data, function(error, result){
    if (error) {
      console.log('Error:'+ error);
    }else{
      console.log(result.result.n);
    }
    db.close();
  })
}
Copy after login

Stored procedures

Create stored procedures in mongodb

All stored procedures are stored in db.system.js , call the stored procedure through db.eval("stored procedure ID()");

Call in code:

var MongoClient = require("mongodb").MongoClient;
var DB_URL = "mongodb://localhost:27017/chm";
 
MongoClient.connect(DB_URL, function(error,db){
  console.log("连接成功!");
  callProcess(db)
});
 
function callProcess(db)
{
  db.eval("get_vip_count()",function(error, result){
    if (error) {
      console.log(error);
    }else{
      console.log("count:"+result);
    }
    db.close();
  });
}
Copy after login


Related labels:
source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template