mongoDB 分页查询数据

[腿毛1米5的欧巴]

需求：做一个前端分页，前端传过来page，和pageSize，然后后端从数据库拿出对应的数据。
下图是我的代码，请问这个查询条件应该怎么写，数据库里面的数据没有排序的id，我该怎么判断数据库中latest 那个值。
{ "_id" : ObjectId("5b62aacd78376a44aa022ab7"), "name" : "cat0", "age" : "age0" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ab8"), "name" : "cat1", "age" : "age1" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ab9"), "name" : "cat2", "age" : "age2" }
{ "_id" : ObjectId("5b62aacd78376a44aa022aba"), "name" : "cat3", "age" : "age3" }
{ "_id" : ObjectId("5b62aacd78376a44aa022abb"), "name" : "cat4", "age" : "age4" }
{ "_id" : ObjectId("5b62aacd78376a44aa022abc"), "name" : "cat5", "age" : "age5" }
{ "_id" : ObjectId("5b62aacd78376a44aa022abd"), "name" : "cat6", "age" : "age6" }
{ "_id" : ObjectId("5b62aacd78376a44aa022abe"), "name" : "cat7", "age" : "age7" }
{ "_id" : ObjectId("5b62aacd78376a44aa022abf"), "name" : "cat8", "age" : "age8" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac0"), "name" : "cat9", "age" : "age9" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac1"), "name" : "cat10", "age" : "age10" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac2"), "name" : "cat11", "age" : "age11" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac3"), "name" : "cat12", "age" : "age12" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac4"), "name" : "cat13", "age" : "age13" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac5"), "name" : "cat14", "age" : "age14" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac6"), "name" : "cat15", "age" : "age15" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac7"), "name" : "cat16", "age" : "age16" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac8"), "name" : "cat17", "age" : "age17" }
{ "_id" : ObjectId("5b62aacd78376a44aa022ac9"), "name" : "cat18", "age" : "age18" }
{ "_id" : ObjectId("5b62aacd78376a44aa022aca"), "name" : "cat19", "age" : "age19" }


let selectData = function (db, callback) {
//链接数据库文档
let collection = db.collection('news');
//查询数据
let whereStr = {"length": {$gt: latestNum}};
collection.find(whereStr).limit(10).toArray(function (err, result) {
if (err) {
console.log('Error' + err);
return;
}
callback(result);
})
};