To sort, use $sort in MongoDB. Let us create a collection with documents −
> db.demo236.insertOne({"details":{"Name":"Chris","Age":21}}); { "acknowledged" : true, "insertedId" : ObjectId("5e419015f4cebbeaebec514c") } > db.demo236.insertOne({"details":{"Name":"David","Age":23}}); { "acknowledged" : true, "insertedId" : ObjectId("5e41901cf4cebbeaebec514d") } > db.demo236.insertOne({"details":{"Name":"Bob","Age":24}}); { "acknowledged" : true, "insertedId" : ObjectId("5e419023f4cebbeaebec514e") }
Display all documents from a collection with the help of find() method −
> db.demo236.find();
This will produce the following output −
{ "_id" : ObjectId("5e419015f4cebbeaebec514c"), "details" : { "Name" : "Chris", "Age" : 21 } } { "_id" : ObjectId("5e41901cf4cebbeaebec514d"), "details" : { "Name" : "David", "Age" : 23 } } { "_id" : ObjectId("5e419023f4cebbeaebec514e"), "details" : { "Name" : "Bob", "Age" : 24 } }
Following is the query to sort, select and query subdocument in MongoDB −
> db.demo236.aggregate( ... [ ... { $unwind: "$details" }, ... { $project: { ... Name: '$details.Name', ... Age: '$details.Age' ... ... }}, ... { $sort: {Name: -1}} ...] ...);
This will produce the following output −
{ "_id" : ObjectId("5e41901cf4cebbeaebec514d"), "Name" : "David", "Age" : 23 } { "_id" : ObjectId("5e419015f4cebbeaebec514c"), "Name" : "Chris", "Age" : 21 } { "_id" : ObjectId("5e419023f4cebbeaebec514e"), "Name" : "Bob", "Age" : 24 }