Based on http://docs.mongodb.org/manual/reference/command/eval/ and http://docs.mongodb.org/manual/reference/method/db.eval/, eval is deprecated in 3.0.

DB#eval and DB#doEval should be marked as deprecated. Also, I would really appreciate comments suggesting what to use instead of eval.

To quote the existing comments: eval "Evaluates JavaScript functions on the database server. This is useful if you need to touch a lot of data lightly, in which case network transfer could be a bottleneck."

What is a good alternative to this?