Relational vs Non-Relational Databases

Learn about relational and nonrelational databases, what they are, the differences between them, and their comparative advantages in helping you to expertly process data.

The process a computer uses to access a database via structure, table-like methods of relational databases or the varied methods of nonrelational databases.
Table of Contents
  1. Relational databases
  2. Non-relational databases
  3. References

As we have mentioned in our article about cloud databases, there are different database types depending on how they operate. This is important, as these different types are designed for different applications. In this article, we will talk about two main types of databases today: relational and non-relational databases.

Relational databases

According to Oracle, a relational database is a type of database that stores and provides access to data points that are related to one another. In order to easily track related data, a relational database stores data points along with their attributes in the form of tables. The relationship between each piece of data can easily be determined from its location in the table.

A table visualizing a relational database.
A table visualizing a relational database. Image source

To explain how relational databases work, let us use the spreadsheet as an analogy. For spreadsheets, we store related entries (for example, all sales transactions) in a single sheet. For a single sheet, we define the first column as the name or ID of the data points to be included in each row. Each succeeding column contains the  attributes of these data points and are labeled accordingly.

A relational database works similarly:

A relational database will contain at least two relations. These relations contain a different set of attributes but have the same column containing the name or ID, which serves as the connection between seemingly dissimilar relations.

The use of tables, according to Oracle, made it possible to quickly search information through the relations stored in the database. This is why relational databases are one of the most common types of databases in use. One of the most popular implementations of a relational database is the Structured Query Language, or SQL. 

Infoworld lists the following strengths of a relational database:

While the weaknesses are as follows:

InfoWorld concludes that relational databases work best for highly structured data and automation of processes.

Non-relational databases

To clarify further why non-relational databases exist, let us do a quick recap of what structured and unstructured data means. 

Structured data is a type of data that is clearly defined and systematically stored in an easily-searchable format. Examples of structured data include personal information records, business transaction records, and customer records.

Unstructured data is a type of data that is not easily searchable and is stored in a variety of formats that cannot be easily processed. Examples of unstructured data include document files, images, and videos.

Databases were initially developed to store structured data.Relational databases, due to their structurally-optimized capabilities, were the perfect method for storing such data. However, recent developments in modern industries have led to a greater need for storing unstructured data types. Non-relational databases were developed for this purpose. We will highlight five types of non-relational databases:

Summary

Seeing that there is a wide variety of database types now available, you would need to determine the type of data that you need to store so you can make a good choice. Below is a quick summary of each type of data along with the database type they are best designed for:

  1. Highly-structured data that can be stored in tables with fixed number of columns: relational database
  2. Structured data but may have a varying number of columns: wide-column stores
  3. Huge amounts of a single type of data: key-value databases
  4. A structured dataset where each tuple is stored separately: document databases
  5. Highly-interconnected data: graph databases
  6. Time-dependent data: time-series databases

Each type of database has its strengths and you can choose the database type that best fits your individual needs.

Related Articles

-Database Basics: Everything You Need to Know

-Cloud Databases

-Unstructured Data: How to Deal With It

References

What Is a Relational Database

What is a Relational Database Management System?

How to choose the right database for your enterprise

ACID Explained: Atomic, Consistent, Isolated & Durable – BMC Software | Blogs

What is NoSQL? NoSQL Databases Explained

Structured vs Unstructured Data: 5 Key Differences

Wide-column store

https://en.wikipedia.org/wiki/Key–value_database

What is NoSQL? NoSQL Databases Explained

Non-relational data and NoSQL - Azure Architecture Center

Relational databases vs Non-relational databases

Relational vs. Non-Relational Database: Pros & Cons | The Aloa Blog

What is NoSQL? | Nonrelational Databases, Flexible Schema Data Models | AWS

Difference between time-series database and relational database