How to Page in MongoDB

1. Paging in MongoDB
2. Working on Pagination in MongoDB
3. Different Ways to Paginate MongoDB Database

In this article, pagination in MongoDB is discussed in detail. Moreover, the uses and working of pagination in MongoDB are also discussed in brief detail.

Finally, different methods are explained to do paging in MongoDB.

The table of contents for this article is as follows:

1. Paging in MongoDB
2. Working on pagination in MongoDB
3. Different ways to paging in MongoDB

Paging in MongoDB

MongoDB is a popular NoSQL database that manages data in JSON-type documents housed within a collection. It may be required to recover only a few documents at times, or you may seek a clean output.

The pagination phenomenon is utilized in MongoDB to provide readable output. Pagination is a method of displaying vast amounts of disorganized data in a page format.

When compared to the usual techniques of MongoDB, the result may be fetched faster with the aid of pagination.

MongoDB pagination provides an effective technique to describe the data, making paging fast and efficient; in MongoDB, you can rapidly examine many data.

The essential application of paging implementation is that it uses skip, limit, and sort at the database level; however, limit and skip have various issues when used at the database level.

Pagination is just the process of retrieving the next page by utilizing the previous page. In MongoDB, you may establish an index on the collections field to speed up data access.

Methods of Pagination:

1. Using the skip() and limit() method
2. Using the find() and limit() method
3. Pagination using the $slice method
4. Pagination by creating an index
5. Pagination by using the sort() method
6. Pagination by using the range queries

Working on Pagination in MongoDB

1. MongoDB is a document-based database, so pagination is a very important use case while using MongoDB.

2. When you paginate the response in MongoDB, your document result is obvious and in an understandable format.

3. To paginate the MongoDB database, the following scenarios have been used.

   3.1. Process the batch file
   3.2. To show a large number of results set on the user screen or interface

4. You cannot consider client and server-side pagination in MongoDB because it’s very expensive compared to other options.

5. You are handling pagination at the database level, and also you are optimizing your databases to do pagination at the database level.

Different Ways to Paginate MongoDB Database

Using the Find() and the limit() Method

MongoDB’s limit method indicates the maximum amount of documents. The number of pages is supplied as a numeric integer, and when the query hits the limit, the result is printed.

To use the limit method in MongoDB, use the syntax shown below.

db.collection-name.find().limit()

The collection name in the syntax must be substituted with the name of the collection to which this method is to be applied. Whereas the find() function returns all documents, the limit() method is used to restrict the number of documents returned.

For example, the following command will only publish the first three items from the students collection.

db.students.find().limit(3).pretty()

Using the limit() With the skip() Method

To come under the pagination phenomena of MongoDB, employ the limit method in conjunction with the skip() function. As previously noted, the earlier limit technique displays a collection’s maximum number of documents.

In contrast, the skip() method is useful for ignoring the number of documents supplied in a collection. And the result is more refined when the limit() and skip() methods are utilized.

The syntax for using the limit() and skip() methods is as follows.

db.Collection-name.find().skip().limit()

Where skip() and limit() only take numeric values.

The command listed below will carry out the following actions.

1. skip(2) - This method will skip the first two documents from the students collection.
2. limit(3) - After skipping the first two documents, the next three documents will be printed.

db.students.find().skip(2).limit(3)

Using Range Queries

As the name implies, this query processes documents based on a range of any field. The syntax for using range queries is as follows.

db.collection-name.find().min({_id: }).max({_id: })

The following example displays the documents in the students collection that fall between 3 and 5. The output is seen to begin with value(3) of the min() function and finish before value(5) of the max() method.

db.students.find().min({_id: 3}).max({_id: 5})

Using the sort() Method

Use the sort() function to reorder the documents in a collection. The layout can be arranged in either ascending or descending order.

The syntax for using the sort method is as follows.

db.collection-name.find().sort({<field-name>: <1 or -1>})

The field name can be any field to organize documents based on that field, and you can insert 1 for ascending order arrangements and -1 for descending order arrangements.

The command used above will sort the documents in the students collection in descending order by the _id field.

db.students.find().sort({id: -1})

Using the $slice Operator

In the find method, the $slice operator is used to trim a few elements from a single field of all documents and show only those documents.

db.collection-name.find({<field-name>, {$slice: [<num>, <num>]}})

You’ve made another staff collection with an array field for this operator. Using MongoDB’s $slice operator, the following command will display the number of two values from the random field of the staff collection.

In the following command, 1 skips the first value of the random field, while 2 displays the next 2 values after skipping.

db.staff.find({},{random: {$slice: [1,2]}})

Using the createIndex() Method

The index is essential for retrieving documents in the shortest amount of time. When an index is formed on a field, the query uses the index number to identify the fields rather than traversing the entire collection.

The following is the syntax for creating an index.

db.collection-name.createIndex({<field-name>: <1 or -1>})

The <field-name> can be any field, but the order value(s) is always the same. The command here will construct an ascending index on the name field of the students collection.

db.students.createIndex({name: 1})

MongoDB is well-known for its unique support for document storage and retrieval. Database Administrators can use pagination in MongoDB to retrieve documents in an understandable and attractive format.

This article has shown you how the paging phenomena work in MongoDB. MongoDB has numerous methods and operators for this, detailed with examples here.

Each method has its techniques for retrieving documents from a database collection. You may choose any of these options that best suit your needs.