node.js - why mongoose doesn't change mongodb -

my mongdb started by: sudo mongod --port 27111

but mongoose code() doesnt work on mongodb, nothing in mongodb changed mongo shell point of view.

$mongo 127.0.0.1:27111/foo -- insert -- mongodb shell version: 2.4.9 connecting to: 127.0.0.1:27111/foo

show dbs local 0.078125gb show dbs local 0.078125gb

var mongoose = require('mongoose'); var db       = mongoose.createconnection('mongodb://127.0.0.1:27111/foo');  var schema = mongoose.schema; var tasks = new schema({   project: string,   description: string, }); mongoose.model('task', tasks);  var task =mongoose.model('task');  var task = new task();      task.project = 'bikeshed'; task.description = 'paint bideshed red.'; task.save(function(err){   //save   if(err) throw err;   console.log('task saved'); });   //搜索文档 task.find({"project": 'bikeshed'}, function(err, tasks) {   (var = 0 ; < task.length ; i++) {     console.log('--------------id:' + tasks[i]._id);   } });  mongoose.disconnect(); 

instead of mongoose.createconnection, use mongoose.connect

var db = mongoose.connect('mongodb://127.0.0.1:27111/foo');