MongoDB, Mongoose - slow query when retrieving 10k + documents

Question

I have a MongoDB database with 10-12k documents in the collection, and I get very slow queries when trying to get all the documents, for example:

Sales.find()
    .where('author').equals(author)
    .where('date').gt(startDate.unix()).lt(endDate.unix())
    .exec(function(err, results) {
        callback();
    });

This request retrieves about 10.5 thousand documents, and it takes 1000-1300 ms to complete it. I tried to remove the "where" conditions - it only slows down (more documents delivered?).

Does the problem come from Mongoose, MongoDB, JavaScript, or Node? I used the PHP / MySQL database, and it was 10-20 times faster in similar conditions, for example, fetching 10k + rows of data. What am I doing wrong?

EDIT

Sales Scheme:

var salesSchema = new Schema({
    author: String,
    kind: String,
    productID: String,
    description: String,
    date: String,
    amount: String,
    transactionID: {
        type: String,
        unique : true
    }
});

The result of a request from the RoboMongo desktop client:

db.getCollection('sales').find({}).explain()

executionTimeMillis: 46
nReturned: 10359

Answer 1

. find() Mongoose Documents, . lean() , JavaScript, 10k + 3-5 .

Sales.find()
    .where('author').equals(author)
    .where('date').gt(startDate.unix()).lt(endDate.unix())
    .lean()
    .exec(function(err, results) {
        callback();
    });

: http://www.tothenew.com/blog/high-performance-find-query-using-lean-in-mongoose-2/