Efficient pagination of MongoDB aggregation?

Question

For efficiency, the Mongo documentation recommends that limit statements immediately follow sort statements, thus ending up with the somewhat nonsensical:

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Answer 1

In MongoDB cursor methods (i.e. when using find()) like limit, sort, skip can be applied in any order => order does not matter. A find() returns a cursor on which modifications applied. Sort is always done before limit, skip is done before limit as well. So in other words the order is: sort -> skip -> limit.

Aggregation framework does not return a DB cursor. Instead it returns a document with results of aggregation. It works by producing intermediate results at each step of the pipeline and thus the order of operations really matters.

I guess MongoDB does not support order for cursor modifier methods because of the way it's implemented internally.

You can't paginate on a result of aggregation framework because there is a single document with results only. You can still paginate on a regular query by using skip and limit, but a better practice would be to use a range query due to it's efficiency of using an index.

UPDATE:

Since v2.6 Mongo aggregation framework returns a cursor instead of a single document. Compare: v2.4 and v2.6.