I want to update avg field every time when updating star.
{
_id : "001",
star: {
avg: 2.6
count: 3,
_1: 1,
_2: 0,
_3: 1,
_4: 1,
_5: 0,
}
}
How can I update avg field ?
// `avg` should update to number 2 where { count: 2, _1: 1, _3: 1 }
db.Collection.updateOne({_id:"001"},{ $inc:{ "star._4": -1 , "star.count": -1 }})
// `avg` should update to number 3.5 where { count: 2, _4: 1, _3: 1 }
db.Collection.updateOne({_id:"001"},{ $inc:{ "star._1": -1 , "star._4": 1 }})