官網(wǎng): https://mongoosejs.com

connect

只連接一個(gè)數(shù)據(jù)庫(kù)時(shí)可使用這種方式(連接的是默認(rèn)連接)

connect(uri(s), [options], [callback])

var mongoose = require('mongoose');
mongoose.connect('mongodb://user:pass@localhost:port/database');
mongoose.connection.on('error', () => {
  console.log('Mongoose connection error')
});
mongoose.connection.on('open', () => {
  console.log('Mongoose connection success')
});
//
var Schema = new mongoose.Schema({
});
var Model = mongoose.model('xxxx', Schema);

createConnection

需要連接多個(gè)數(shù)據(jù)庫(kù)時(shí)必須使用這種方式(是一個(gè)連接實(shí)例)

createConnection([uri], [options])

var mongoose = require('mongoose');
var db  = mongoose.createConnection('mongodb://user:pass@localhost:port/database');
db.on('error', () => {
  console.log('Mongoose connection error')
});
db.on('connected', () => {
  console.log('Mongoose connection success')
});
//
var Schema = new mongoose.Schema({
});
var Model = db.model('xxxx', Schema);// 這里必須使用db不能是mongoose