Template
single collection
multiple collections
mgodatagen
update
indexe
explain
Stage
Database
bson
mgodatagen
[{"timestamp":"1","data":{"field1":1,"field2":2,"fieldN":3}}]
Query
db.collection.aggregate([{$replaceRoot:{newRoot:{$mergeObjects:["$$ROOT","$data"]}}},{$project:{data:0}}])
Result