What is Document Database - MongoDB Tutorial

It is a type of nonrelational DB that is designed to store and query data as JSON-like documents.
It becomes easier for developers to store and query data in a database while using the same document-model format they use in their application code.
In document databases the data stored documents with their metadata.
The key is the unique identifier of the document where the document stored is in key/value pair.
Document databases are quicker to load, access, and parse.

For Example

It provides fast queries, a structure well suited for handling big data.
Flexible indexing and a simplified method of maintaining the database.
It has been fully integrated by large-scale IT companies like Amazon and it is efficient for web apps.
It easy to query data with the same document-model used to code the application.

No restrictions in the format and structure of data storage.
It is good for retaining existing data at big volumes and different structural states, especially in a constantly transforming system.

Minimal maintenance is required once you create the document, which can be as simple as adding your complex object once.

The absence of this relationship dynamic, documents can be independent of one another.

A clean build process that uses XML, JSON and other derivatives to describe documents.

While documents grow in size they can also grow in complexity. It decreases conflicts.

In database we use case example above, it would be possible to search for books from a non-existent author.
You should search the book collection and discover files that aren't linked to an author series.
These inconsistencies aren’t significant in a few contexts, however at upper-tier standards of RDB consistency audits, they seriously hamper database performance.

Relational systems also allow you to modify data from one place without the need for JOINs.
A change involving two collections will require you to run two separate queries (per collection) for document databases.
Breaks atomicity requirements.

For Web application security owners of NoSQL databases, therefore, want to pay careful attention.
Nearly half of web applications today actively leak sensitive data.