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MongoDB limit()


In MongoDB, limit() method is used to limit the fields of document that you want to show. Sometimes, you have a lot of fields in collection of your database and have to retrieve only 1 or 2. In such case, limit() method is used.

The MongoDB limit() method is used with find() method.

Syntax:

  1. db.COLLECTION_NAME.find().limit(NUMBER)

Scenario:

Consider an example which has a collection name Kreationnext.

This collection has following fields within it.

  1. [
  2.   {
  3.     Course: “Java”,
  4.     details: { Duration: “6 months”, Trainer: “Sonoo Jaiswal” },
  5.     Batch: [ { size“Medium”, qty: 25 } ],
  6.     category: “Programming Language”
  7.   },
  8.   {
  9.     Course: “.Net”,
  10.     details: { Duration: “6 months”, Trainer: “Prashant Verma” },
  11.     Batch: [ { size“Small”, qty: 5 }, { size“Medium”, qty: 10 }, ],
  12.     category: “Programming Language”
  13.   },
  14.   {
  15.     Course: “Web Designing”,
  16.     details: { Duration: “3 months”, Trainer: “Rashmi Desai” },
  17.     Batch: [ { size“Small”, qty: 5 }, { size“Large”, qty: 10 } ],
  18.     category: “Programming Language”
  19.   }
  20. ];

Here, you have to display only one field by using limit() method.

Example

  1. db.Kreationnext.find().limit(1)

After the execution, you will get the following result

Output:

{ "_id" : ObjectId("564dbced8e2c097d15fbb601"), "Course" : "Java", "details" : {
 "Duration" : "6 months", "Trainer" : "Sonoo Jaiswal" }, "Batch" : [ { "size" :
"Medium", "qty" : 25 } ], "category" : "Programming Language" } 

MongoDB skip() method

In MongoDB, skip() method is used to skip the document. It is used with find() and limit() methods.

Syntax

  1. db.COLLECTION_NAME.find().limit(NUMBER).skip(NUMBER)

Scenario:

Consider here also the above discussed example. The collection Kreationnext has three documents.

  1. [
  2.   {
  3.     Course: “Java”,
  4.     details: { Duration: “6 months”, Trainer: “Sonoo Jaiswal” },
  5.     Batch: [ { size“Medium”, qty: 25 } ],
  6.     category: “Programming Language”
  7.   },
  8.   {
  9.     Course: “.Net”,
  10.     details: { Duration: “6 months”, Trainer: “Prashant Verma” },
  11.     Batch: [ { size“Small”, qty: 5 }, { size“Medium”, qty: 10 }, ],
  12.     category: “Programming Language”
  13.   },
  14.   {
  15.     Course: “Web Designing”,
  16.     details: { Duration: “3 months”, Trainer: “Rashmi Desai” },
  17.     Batch: [ { size“Small”, qty: 5 }, { size“Large”, qty: 10 } ],
  18.     category: “Programming Language”
  19.   }
  20. ];

Execute the following query to retrieve only one document and skip 2 documents.

Example

  1. db.Kreationnext.find().limit(1).skip(2)

After the execution, you will get the following result

Output:

{ "_id" : ObjectId("564dbced8e2c097d15fbb603"), "Course" : "Web Designing", "det
ails" : { "Duration" : "3 months", "Trainer" : "Rashmi Desai" }, "Batch" : [ { "
size" : "Small", "qty" : 5 }, { "size" : "Large", "qty" : 10 } ], "category" : "
Programming Language" }

As you can see, the skip() method has skipped first and second documents and shows only third document.

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