db={"users":[{_id:"123"},{_id:"456"}],"questions":[{authorId:"123",createdAt:ISODate("2022-09-01T00:00:00Z")},{authorId:"456",createdAt:ISODate("2022-09-05T00:00:00Z")},],"answers":[{authorId:"123",createdAt:ISODate("2022-09-01T08:00:00Z")},{authorId:"456",createdAt:ISODate("2022-09-05T08:00:00Z")},],"comments":[{authorId:"123",createdAt:ISODate("2022-09-01T16:00:00Z")},{authorId:"456",createdAt:ISODate("2022-09-05T16:00:00Z")},],}

db.users.aggregate([{"$lookup":{"from":"questions","let":{id:"$_id"},"pipeline":[{"$match":{$expr:{"$and":[{"$gt":["$createdAt",ISODate("2022-09-03T00:00:00Z")]},{"$eq":["$$id","$authorId"]}]}}}],"as":"questions"}},{"$lookup":{"from":"answers","let":{id:"$_id"},"pipeline":[{"$match":{$expr:{"$and":[{"$gt":["$createdAt",ISODate("2022-09-03T00:00:00Z")]},{"$eq":["$$id","$authorId"]}]}}}],"as":"answers"}},{"$lookup":{"from":"comments","let":{id:"$_id"},"pipeline":[{"$match":{$expr:{"$and":[{"$gt":["$createdAt",ISODate("2022-09-03T00:00:00Z")]},{"$eq":["$$id","$authorId"]}]}}}],"as":"comments"}},{"$project":{"questionCount":{"$size":"$questions"},"answersCount":{"$size":"$answers"},"commentsCount":{"$size":"$comments"}}}])