MongoDB - Aggregation Framework (Total Count)

Question

When running a normal \"find\" query on MongoDB I can get the total result count (regardless of limit) by running \"count\" on the returned cursor. So, even if I limit to re

Answer 1

If you don't want to run two queries in parallel (one to aggregate the #posts for your top authors, and another aggregation to calculate the total posts for all authors) you can just remove $limit on pipeline and on results you can use

totalCount = results.length;
results.slice(number of skip,number of skip + number of limit);

ex:

db.article.aggregate([
    { $group : {
        _id : "$author",
        posts : { $sum : 1 }
    }},
    { $sort : { posts: -1 } }
    //{$skip : yourSkip},    //--remove this
    //{ $limit : yourLimit }, // remove this too
]).exec(function(err, results){
  var totalCount = results.length;//--GEt total count here
   results.slice(yourSkip,yourSkip+yourLimit);
});