Database
[{item:"Car",startdate:ISODate("2022-03-31T15:30:00Z"),enddate:ISODate("2022-03-31T16:00:00Z")},{item:"Bike",startdate:ISODate("2022-03-31T15:30:00Z"),enddate:ISODate("2022-03-31T16:00:00Z")}]
Query
db.collection.aggregate([{$match:{item:{"$in":["Car","Truck"]}}},{$set:{diff:{$dateDiff:{startDate:"$startdate",endDate:"$enddate",unit:"minute"}}}}])