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MongoDB query to change order of array elements?
Use swap concept to change the order of array elements. Let us create a collection with documents −
> db.demo301.insertOne({"Name":["Chris","David","Bob"]});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e4d6ff55d93261e4bc9ea51")
}Display all documents from a collection with the help of find() method −
> db.demo301.find();
This will produce the following output −
{ "_id" : ObjectId("5e4d6ff55d93261e4bc9ea51"), "Name" : [ "Chris", "David", "Bob" ] }Following is the query to change the order of array elements −
> db.demo301.find({}, { Name : 1 }).forEach(function(n) {
... var t = n.Name[0];
... n.Name[0] = n.Name[1];
... n.Name[1] = t;
... db.demo301.update({ _id: n._id }, { $set: { Name: n.Name } });
...})Display all documents from a collection with the help of find() method −
> db.demo301.find();
This will produce the following output −
{ "_id" : ObjectId("5e4d6ff55d93261e4bc9ea51"), "Name" : [ "David", "Chris", "Bob" ] }
Updated on: 01-Apr-2020
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