Template
single collection
multiple collections
mgodatagen
update
indexe
explain
Stage
Database
bson
mgodatagen
[{"rows":[["123","234","345"],["345","456","567"]]},{"rows":[["111","222","333"],["444","555","345"]]}]
Query
db.collection.aggregate([{"$match":{"rows":{"$elemMatch":{"$elemMatch":{"$eq":"345"}}}}}])
Result