MongoDB aggregate by field exists

Question

I have a hard time believing this question hasn\'t been asked and answered somewhere already, but I can\'t find any trace of it.

I have a MongoDB aggregation query t

Answer 1

Dunno how it was but now in 2019 there is clean solution. In aggregation pipeline do this

$match: {"my_field": {$ne: null}}

Nice thing is in my lang 'ne' means not :)