问题 This question already has answers here : Retrieve only the queried element in an object array in MongoDB collection (11 answers) Closed last year . How can I query (in MongoDB) this nested json structure in order to get only the nested object which has the "position" value equal to "currentPosition" value? { "JobId": "123" "currentPosition" : NumberInt(18), "details" : [ { "position": NumberInt(18), "fname" : "Alexander", "lname" : "A", }, { "position": NumberInt(18), "fname" : "Doug", "lname