Template
single collection
multiple collections
mgodatagen
update
indexe
explain
Stage
Database
bson
mgodatagen
[{_id:1,members:[{user:{_id:1}},{user:{_id:2}}]},{_id:3,members:[{user:{_id:3}},{user:{_id:4}}]}]
Query
db.collection.find({"members.user._id":1})
Result