节点回调数据库查询

Question

也许我的PHP大脑不允许我做nodejs所有我想要的功能＆＃34; myfindindb＆＃34;要返回一个值，是否可以使用nodejs？我知道异步，这是不像瀑布一样工作的原因吗？

var MongoClient = require('mongodb').MongoClient;
var assert = require('assert');
var ObjectId = require('mongodb').ObjectID;
var url = 'mongodb://localhost:27017/exampleDb';
var mysite = '';
var myisfound;
var numItems = '';


function myfindindb(mysite) {

    var findRestaurants = function(db, callback) {

        var cursor = db.collection('restaurants').find({
            "site": mysite
        }).limit(1);

        cursor.each(function(err, doc) {

            assert.equal(err, null);

            var myresults = doc.site;

            return callback(myresults);


        });

       };

    MongoClient.connect(url, function(err, db) {
        assert.equal(null, err);

        findRestaurants(db, function(myresults,callback) {

            console.dir(myresults); //as far as Iv got goo so far

            db.close();

            return callback(myresults); //this bit wont work??
        });


    });

}


var foo = myfindindb('http://google.com');
console.log(foo);