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MongoDB query to get only a specific number of elements
To return only a specific number of elements, use aggregate() and $slice. Let us create a collection with documents −
> db.demo75.insertOne({"Name":["Sam","Mike","Carol","David","Bob","John"]});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e2bcd7671bf0181ecc42278")
}Display all documents from a collection with the help of find() method −
> db.demo75.find();
This will produce the following output −
{ "_id" : ObjectId("5e2bcd7671bf0181ecc42278"), "Name" : [ "Sam", "Mike", "Carol", "David", "Bob", "John" ] }Following is the slice query in MongoDB −
> db.demo75.aggregate([ { $project: { Name: { $slice: [ "$Name", 4 ] } } } ]);This will produce the following output −
{ "_id" : ObjectId("5e2bcd7671bf0181ecc42278"), "Name" : [ "Sam", "Mike", "Carol", "David" ] }
Updated on: 30-Mar-2020
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