mongodb - Not able to write the query in mongo for array element match? -

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i working on project on had make recommendation system users in website.i new mongodb. want retrieve names/id of users have "frnds.type"=1 in below code.

{ "_id" : objectid("56a9fcc15b4e12369150d6ef"), "name" : "udit", "venue" : {     "state" : "rajasthan",     "city" : "jaipur",     "ll" : [         "26.9000",         "75.8000"     ] }, "lsv" : [     0.14,     0.18,     0.24,     0.17,     0.05,     0.17,     0.05 ], "username" : "udit", "frnds" : [     {         "id" : "amit",         "type" : 1     },     {         "id" : "nakul",         "type" : 0     },     {         "id" : "verma",         "type" : 1     } ]

}

i have written 1 query giving wrong results 

db.users.find({"username":"udit"},{"frnds":{"$elemmatch":{"type":1}}}).pretty()

i want result in manner :

[ { "id":"amit", "type":1 }, { "id":"verma", "type":1 } ]

try aggregation framework below.

 db.users.aggregate([{     $match: {username: 'udit'},      {$unwind: '$frnds'},      {$match: {'frnds.type': 1}},      {$group: {frnds: {$push: "$frnds"}}  }]);

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