start mongo db and write create collection in nodejs | nodejs tutorials

 write mongo db and conncec to server

var mongoose= require("mongoose");

mongoose.connect('mongodb://localhost:27017/mydatabase' ,

{

useNewUrlParser: true,

useUnifiedTopology: true

})

.then((res) => {

console.log(

'connected'

);

})

.catch((err) => {

console.log(

`not connected`,

err

);

});

ist start the mongo db server

then import the mongodb

connect to server

if it is connect it will print connect otherwise not connected

in below program 

connect to mongodb and if eror show this 

if open show this

var db = mongoose.connection;

db.on('error',console.error.bind(console,'connection error'));

db.on('open', function(){

console.log('connected');

});