Template
single collection
multiple collections
mgodatagen
update
indexe
explain
Stage
Database
bson
mgodatagen
[{"group":"1,2,3,6"},{"group":"1,2,3"}]
Query
db.collection.aggregate([{"$match":{"group":{"$regex":"6"}}},{"$set":{"group":{"$replaceAll":{"input":"$group","find":"6","replacement":""}}}}])
Result