mongodb - snapshot option of find method not working -

my code

method 1:

... var cursor = collection.find({}, {snapshot: true}); //i made sure insert new document collection before below timer fires settimeout(function(){     cursor.each(function(err, docu){         console.log("cursor items", docu);     }) }, 15000); 

method 2:

var cursor = collection.find({}, {snapshot: true}); cur.nextobject(function(err, item) {     console.log("read first doc alone", item) }) //i made sure insert new document collection before below timer fires settimeout(function(){     cursor.each(function(err, docu){         console.log("cursor items", docu);     }) }, 15000); 

for both methods, started application, within next 15 secs inserted row same db manually.

method 1 outputs rows exists , row inserted in 15 secs.

method 2 outputs first row , method not printing row inserted in 15 secs, irrespective of {snapshot: true} or {snapshot: false}

questions

1. why 'snapshot' option of find method not working in method 1
2. giving {snapshot: true} or {snapshot: false} in method 2 not prints document inserted manually.
3. please let me know site, explains behavior of cursors.

tried per @scott hernandez below, newly inserted documents coming in snapshot cursor.

var simpleschema = new mongoose.schema({     name:{type:string} }, {collection:'simple'}); var simplemodel = mongoose.model('simplemodel', simpleschema);  //var snapshotquery = simplemodel.find({}).setoptions({snapshot:true}); //try method 1 var snapshotquery = simplemodel.find({}).snapshot(true);                //try method 2  settimeout(function(){     snapshotquery.exec(function(err, docs){         if(err){             console.log("error", err);         }else{             console.log("settimeout", docs);         }     }) },10000) 

the format incorrect. must use snapshot method described in docs.