Mongodb: aggregate $match only if object is empty

Question

I want to $match only the empty objects in my aggregate(). Is it possible? I know of $exists, but {}'s boolean value is true, so I'm stuck.

Alan Mroczek · Accepted Answer · 2017-01-09 10:51:23Z

6

Have you tried to just use {field: {}} ?

For example:

db.users.aggregate([{$match: {val: {}}}])

answered Jan 9, 2017 at 10:51

Alan Mroczek

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2 Comments

Thanks, easier than I thought.

How can I do the opposite and match only no empty result ?