Node.js và Mongodb hướng dẫn kết nối

//lets require/import the mongodb native drivers.
var mongodb = require('mongodb');

//We need to work with "MongoClient" interface in order to connect to a mongodb server.
var MongoClient = mongodb.MongoClient;

// Connection URL. This is where your mongodb server is running.
var url = 'mongodb://localhost:27017/test';

// Use connect method to connect to the Server
MongoClient.connect(url, function (err, db) {
if (err) {
console.log('Unable to connect to the mongoDB server. Error:', err);
} 
else 
{
//HURRAY!! We are connected.
console.log('Connection established to', url);

// Get the documents collection
var collection = db.collection('zips');

// Find some state
collection.find({'state': 'MA'}).toArray
(

function (err, result) {
if (err) {
console.log(err);
} else if (result.length) {
console.log(result);
//var result=result.length;

} else {
console.log('No document(s) found with defined "find" criteria!');
}
//Close connection
db.close();
}

);
}
});

//lets require/import the mongodb native drivers.
var mongodb = require('mongodb');

//We need to work with "MongoClient" interface in order to connect to a mongodb server.
var MongoClient = mongodb.MongoClient;

// Connection URL. This is where your mongodb server is running.
var url = 'mongodb://localhost:27017/test';

// Use connect method to connect to the Server
MongoClient.connect(url, function (err, db) {
if (err) {
console.log('Unable to connect to the mongoDB server. Error:', err);
} 
else 
{
//HURRAY!! We are connected. :)
console.log('Connection established to', url);

// Get the documents collection
var collection = db.collection('zips');
//Create some document
var smartjob1 = {city: 'smartjob.vn', pop: 1242, state: 'MA', loc: [-72.936114, -72.936114]};
var smartjob2 = {city: 'mang tuyen dung hang dau viet nam', pop: 3442, state: 'MA', loc: [42.182949, 42.182949]};

// Insert some users
collection.insert([smartjob1, smartjob2], function (err, result) {
if (err) {
console.log(err);
} else {
console.log('Inserted %d documents into the "users" collection. The documents inserted with "_id" are:', result.length, result);
}
//Close connection
db.close();
});

}
});

//lets require/import the mongodb native drivers.
var mongodb = require('mongodb');

//We need to work with "MongoClient" interface in order to connect to a mongodb server.
var MongoClient = mongodb.MongoClient;

// Connection URL. This is where your mongodb server is running.
var url = 'mongodb://localhost:27017/test';

// Use connect method to connect to the Server
MongoClient.connect(url, function (err, db) {
if (err) {
console.log('Unable to connect to the mongoDB server. Error:', err);
} 
else 
{
//HURRAY!! We are connected. :)
console.log('Connection established to', url);

// Get the documents collection
var collection = db.collection('zips');
collection.update({city: 'smartjob.vn'}, {$set: {city: 'smartjob.vn2'}}, function (err, numUpdated) {
if (err) {
console.log(err);
} else if (numUpdated) {
console.log('Updated Successfully %d document(s).', numUpdated);
} else {
console.log('No document found with defined "find" criteria!');
}
//Close connection
db.close();
});
}
});

var mongodb = require('mongodb');

var MongoClient = mongodb.MongoClient;

// Connection URL. This is where your mongodb server is running.
var url = 'mongodb://localhost:27017/test';

// Use connect method to connect to the Server
MongoClient.connect(url, function (err, db) {
if (err) {
console.log('Unable to connect to the mongoDB server. Error:', err);
} 
else 
{
console.log('Connection established to', url);

// Get the documents collection
var collection = db.collection('zips');
// start 
collection.deleteOne({ city : 'smartjob.vn2' }, function(err, result) {
if (err) {
console.log(err);
} else {
console.log('xoa thanh cong');
}
//Close connection
db.close();
}); 
//end 
}
});