Database
db={"Movies":[{"Movie_ID":{"$numberInt":"31"},"Movie_Name":"Tanhajhi","Release_Date":{"$date":{"$numberLong":"1578643200000"}},"Genre":"Action"}],"Ratings":[{"Rating_ID":{"$numberInt":"61"},"Person_ID":{"$numberInt":"11"},"Movie_ID":{"$numberInt":"31"},"Theatre_ID":{"$numberInt":"21"},"Movie_Rating":{"$numberInt":"5"},"Theatre_Rating":{"$numberInt":"2"}}]}
Query
db.Movies.aggregate([{$lookup:{from:"Ratings",localField:"Movie_ID",foreignField:"Movie_ID",as:"M_Ratings"}}])