mongodb - Retrieve only documents with the highest value -

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i want write query finds documents highest value. there multiple documents same value, , want of them.

i know can use sort sort high low. don't know how many documents there are. won't work.

{      total: 1,      id: 1 }, {     total: 1,     id: 2 }, {     total: 2,     id: 3 }, {     total: 2,     id: 4 }, {     total: 3,     id: 5 }, {     total: 3,     id: 6 }

in example want return documents have total 3. how can query documents have highest value?

this work you:

db.yourcollectionname.aggregate([     {         $group:{             _id: null,             high_val: {$max:"$total"}         }     },     {         $lookup:{            from: "yourcollectionname",            localfield: "high_val",            foreignfield: "total",            as: "elements"         }     },     {         $unwind: "$elements"     },     {         $project:{             _id:false,             id: "$elements.id",             total: "$elements.total"         }     } ]);

here $lookup used take max value retrieved initial $group, , apply same table retrieve matching records.

i'm there better way this, couldn't resist, i've started using $lookup, exploring can do.


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