Db.sales.insert (""merchandise ":"jacket ","sales time ":"2015-12-01 11:00 ","selling price ":1.3});
Db.sales.insert (""merchandise ":"jacket ","sales time ":"2015-12-01 12:00 ","selling price ":1.4});
Db.sales.insert (""goods ":"trousers ","sales time ":"2015-12-01 11:30 ","selling price ":2.3});
Db.sales.insert (""goods ":"trousers ","sales time ":"2015-12-01 12:30 ","selling price ":2.4});
Db.sales.insert (""merchandise ":"shoes ","sales time ":"2015-12-01 11:00 ","selling price ":3.3});
Db.sales.insert (""merchandise ":"shoes ","sales time ":"2015-12-01 12:00 ","selling price ":3.4});
Db.sales.insert (""merchandise ":"shoes ","sales time ":"2015-12-01 12:30 ","selling price ":3.5});
db.sales.aggregate([
{ $group: {
_id: "$ commodity ",
"sales": {$sum:1},
"Last Sales Time": {$max: "$ Sales Time "}
} }
]);
Question: How to find the selling price corresponding to the last selling time?
Hope this helps.
Love MongoDB! Have Fun!