Filter list of embedded documents with reference field

问题

I'm pretty new to MongoDB and I'm experiencing it with mongoengine. Given this 'User' model where 'bets' is an embedded document list which each element contains a reference to a 'match' document,

{ 
  "_id" : ObjectId("53df77cef4c9610f28cbff14"), 
  "name" : "Test", 
  "admin" : false, 
  "bets" : [ 
             { "match" : ObjectId("53e1511df4c9610bf52f5b7a"), "expectedResult" : "1" } 
           ] 
 }

how can I get 'bets' elements, passed to query the matchId?

I tried to do

User.objects.filter(bets__match={'match._id':match.id})

where 'match' is the object I need to filter by but I get an empty array.

来源：https://stackoverflow.com/questions/25180853/filter-list-of-embedded-documents-with-reference-field