Mongodb: return matched filters when using $or in find()

Suppose I am doing a query in Mongodb like this

db.user.find({$or : [{"field1" : "abc"}, {"field2" : "def"}, {"field3" : "ghi"}]})

And a number of documents are 开发者_如何学Creturned. What is the easiest way to know which one (or multiple) of the three filters is matched for each document returned? By "easiest", I do not wish to add more executions of find()'s.

Thanks.

There is no such option to solve this on the MongoDB query layer. Likely you want to perform individual queries instead one big $or query in order to solve your problem.