javascript - Find a maximum value in a collection in nodeJS and MongoDb -


i have simple query cant working. have collection named users has uid field. want maximum value of uid field it. following :-

   var options = { "sort": [['uid',-1]] };     db.users.findone({}, options , function(err, doc) {     console.log("returned #" + doc.uid + " documents"); });

but gives me 99 while have values upto 300. guess matching every element 9 , comparing it. correct answer should 314

following way entries saved in collection :-

{   {  _id: "531181a3ec9af9107d2b4ccd",  age: "0",  carmodel: "bullet motorcycle",  chargeprice: "",  contact: "",  email: "",  fbid: "1179803227",  fromlat: "28.4594965",  fromlon: "77.0266383",  fromname: "gurgaon, haryana, india",  fueltype: "petrol",  id: "215",  image: "http://graph.facebook.com/1179803227/picture?type=large",  name: "sandeep yadav",  points: "0",  regid: "abc",  returntime: "15:41 hrs",  sex: "0",   smoking: "no smoking allowed",  starttime: "15:41 hrs",  tolat: "28.510782",  tolon: "77.048646",  toname: "sector 23 ,huda market, huda, sector 23, gurgaon, haryana, india",  uid: 311 }, {  _id: "531181a3ec9af9107d2b4cce",  age: "0",  carmodel: "2014 nissan sentra",  chargeprice: "usd 30",  contact: "",  email: "",  fbid: "100001451156666",  fromlat: "27.950575",  fromlon: "-82.4571776",  fromname: "tampa, fl, united states",  fueltype: "petrol",  id: "214",  image: "http://graph.facebook.com/100001451156666/picture?type=large",  name: "kelly j. dugan",  points: "0",  regid: "abc",  returntime: "23:04 hrs",  sex: "0",  smoking: "doesnt matter",  starttime: "16:02 hrs",  tolat: "25.7889689",  tolon: "-80.2264393",  toname: "miami, fl, united states",  uid: 308 } }

try this:

db.users.find({}).sort("uid":-1).limit(1)

that find users, sort them, , return first one.


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