MongoDB query to skip documents

MongoDBDatabaseBig Data Analytics

To skip documents in MongoDB, use skip(). Let us create a collection with documents −

> db.demo263.insertOne({_id:100});
{ "acknowledged" : true, "insertedId" : 100 }
> db.demo263.insertOne({_id:200});
{ "acknowledged" : true, "insertedId" : 200 }
> db.demo263.insertOne({_id:300});
{ "acknowledged" : true, "insertedId" : 300 }

Display all documents from a collection with the help of find() method −

> db.demo263.find();

This will produce the following output −

{ "_id" : 100 }
{ "_id" : 200 }
{ "_id" : 300 }

Following is the query to skip document −

> result = db.demo263.aggregate([
...   {
...      $project: {
...         v_id: { $ifNull: [null, [100, 200]] }
...
...      }
...   },
...   { $unwind: '$v_id' },
...   { $sort: { v_id: 1, _id: 1 } },
...
...   { $skip: 2 },
...   { $limit: 2 }
...]);

This will produce the following output −

{ "_id" : 300, "v_id" : 100 }
{ "_id" : 100, "v_id" : 200 }
raja
Published on 31-Mar-2020 12:03:40
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