A Simple Introduction to NoSQL Database and Why We Need It

Whether you have worked with databases, are about to work with one, or haven’t worked at all, this topic is something you should know whether to pick a relational or non-relational data structure.

This article includes explanation to help you better understand the meaning of a non relational data structure.

Introduction to NoSQL

As the name suggests NoSQL is “not” SQL, in other words, it is a non-relational database and is unstructured. Due to its unstructured nature, it is sometimes called UnQL

It follows a database design which can take all sorts of data models. It mainly consists of key-value pairs, graphs, documents, etc. It is especially used to store large sets of distributed data.

NoSQL databases are purpose-built for specific data models and have flexible schemas for building modern applications. NoSQL databases are widely recognized for their ease of development, functionality, and performance at scale. While NoSQL databases have existed for many years, NoSQL databases have only recently become more popular in the era of cloud, big data and high-volume web and mobile applications.

Processed data is information. The processed information is knowledge; Processed knowledge is wisdom.

Ankara V. Subbarao

The original DBMSs were flat-file/comma-delimited, often proprietary to a particular application, and limited in the relationships they could uncover among data. As RDBMS have increasingly failed to meet the performance, scalability, and flexibility needs that next-generation, data-intensive applications require, mainstream enterprises have adopted NoSQL databases.

How Does a NoSQL Database Work?

NoSQL databases use a variety of data models for accessing and managing data. These databases are optimised specifically for applications requiring large data volume, low latency, and flexible data models, as described above.

The concept of NoSQL databases became popular with Internet giants like Google, Facebook, Amazon, etc. who deal with huge volumes of data. The system response time becomes slow when you use RDBMS for massive volumes of data. How can NoSQL overcome this bottleneck?

It uses a distributed hardware scaling method called ‘Scale-out’ to distribute the computing among hosts, compared to the Scale-up method, which is expensive and inefficient.

NoSQL database is non-relational, so it scales out better than RDBMS as they are designed with web applications in mind.

Why Should We Use NoSQL

NoSQL databases are a great fit for many modern applications such as mobile, web, and gaming that require flexible, scalable, high-performance, and highly functional databases to provide great user experiences. NoSQL databases also offer enterprises important advantages over traditional RDBMS. Let us look at some of the major benefits of having a NoSQL database to store our data.

Scalability

Scalable database should be a priority when it comes to making technical developments
Scalable database should be a priority when it comes to making technical developments. Source: Markus

NoSQL databases use a horizontal scale-out methodology that makes it easy to add or reduce capacity quickly and non-disruptively with commodity hardware. This eliminates the tremendous cost and complexity of manual sharding that is necessary when attempting to scale RDBMS.

Speed and Performance in Mind

Enterprises can increase performance with NoSQL databases by adding hardware
Enterprises can increase performance with NoSQL databases by adding hardware. Source: Jean

By simply adding hardware resources as described previously, enterprises can increase performance with NoSQL databases. This enables organizations to continue to deliver fast user experiences with a predictable return on investment for adding resources. Some cloud providers have options to handle these operations behind the scenes as a fully managed service to reduce the load and time required to set it up on the client-side.

Data Model that is Flexible

A flexible data model will ensure application developers to take full advantage of it
A flexible data model will ensure application developers to take full advantage of it. Source: Dennis

NoSQL offers the ability to implement flexible and fluid data models. Application developers can leverage the data types and query options that are the most natural fit to the specific application use case rather than those that fit the database schema. The result is a simpler interaction between the application and the database and faster, more agile development. NoSQL databases generally provide flexible schemas that enable faster and more iterative development. The flexible data model makes NoSQL databases ideal for semi-structured and unstructured data.

High Availability

NoSQL databases are generally designed to ensure high availability
NoSQL databases are generally designed to ensure high availability. Source: Leyre

NoSQL databases are generally designed to ensure high availability. Some “distributed” NoSQL databases use a masterless architecture that automatically distributes data equally among multiple resources so that the application remains available for both reads and write operations even when one node fails.

Comparision of NoSQL and SQL

The question of SQL or NoSQL always comes up in this discussion, and this is subjective to the kind of data that is being handled. If you have constantly changed data and the database requires quick scalability, NoSQL is ideal.

In the early days, NoSQL databases often got used for super focused data management tasks. When it came to web and cloud apps, NoSQL has been proven to process and distribute significant volumes of data.

Moreover, in the world of big data, most of the data is unstructured. How can we determine which database to use? Well, it all depends on the use case. Let us look at some of the differences between SQL and NoSQL.

The table above summaries some of the differences between the two database.

Once we have understood the major difference, we cannot still select a type of database to work on. Before making a final decision to select a database to use, it is essential to consider the following aspects:

  • The type of data in question
  • The quantity of data
  • How will the database be maintained

Those questions above will provide a broader understanding of the type of database that is more suitable.

Types of NoSQL Databases

A NoSQL database can manage information using any of four primary data models:

Key-value store

Key-value databases are highly partitionable and allow horizontal scaling at scales that other types of databases cannot achieve. Key-value database store data in a similar way as a simple hash table.

Document

Document databases make it easier for developers to store and query data in a database by using the same document model format that they use in their application code.

Column

Wide-column NoSQL databases store data in tables with rows and columns similar to RDBMS, but names and formats of columns can vary from row to row across the table.

Graphs Database

A graph database’s main purpose is to make it easy to build and run applications that work with highly connected datasets.

Detailed explanation of each of the type of the database will be continued on a another article.

Now, Let’s Summarise

Let us have a quick recap of what we have read in this article.

NoSQL databases are purpose-built for specific data models and have flexible schemas for building modern applications. NoSQL databases are widely recognized for their ease of development, functionality, and performance at scale.

NoSQL databases use a variety of data models for accessing and managing data. These databases are optimised specifically for applications requiring large data volume, low latency, and flexible data models, as described above.

Why should we use NoSQL? NoSQL databases are a great fit for many modern applications such as mobile, web, and gaming that require flexible, scalable, high-performance, and highly functional databases to provide great user experiences.

Today, many applications are delivered as services, and those services must be available 24/7, accessible from a wide range of devices, and scaled to what can potentially be millions of users. NoSQL was created to manage the scale and agility challenges that face modern applications, but the suitability of a database depends on the problem it must solve.

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