Get total count along with Mongoose Query skip & limt

Question

I have a json data which contains many objects. I want to limit the data for pagination and I need the total items count. Please help.

Model.find().skip((pageNumber-1)*limit).limit(limit).exec()

I want the count and skipped data in response.

Answer 1

I have solved it with $facet and aggregate the following way in mongoose v3+:

const [{ paginatedResult, [{ totalCount }] }] = await Model.aggregate([{
  $facet: {
    paginatedResult: [
      { $match: query },
      { $skip: skip },
      { $limit: limit }
    ],
    totalCount: [
      { $match: query },
      { $count: 'totalCount' }
    ]
  }
}])

where the totalCount refers the total number of records matching the search query while the paginatedResult is only the paginated slice of them.

Answer 2

The problem with these solutions is that for every request you are doing two queries. This becomes problematic when you have a complex data structure and large data set as performance becomes an issue. Consider instead creating a special function that listens for the /resource?count=true or /resource/count GET methods and returns only the count.