Relational vs. non-relational databases: Understanding the difference

Before delving into terms like relational vs. non-relational databases, let’s begin with first understanding what exactly a database is and what it does. You may already be familiar with one kind of database or another, but breaking it down into easier terms will help you better understand the two types and which one will work best for your particular needs.

Simply put, a database is a set of data that is stored on a computer and can be accessible in multiple ways. As mentioned above, the two main types of databases are relational and non-relational.

Breaking down relational vs. non-relational databases

Here we unpack the differences between the two databases and why it helps to know their characteristics when choosing between them.

The relational database (RDBMS)

A relational database is a straightforward way of representing data in tables. It is a type of database that stores and then provides access to data points related to one another.For example, in a  relational database, each row in a table is a record with a unique ID called a key. The columns of the table hold attributes of the data. Each record generally has a value for each attribute, making it easy to understand the relationships among data points. Therefore, points of data and all queries would tie to a table, and the table structure would allow for sorting, filtering, calculations, etc.

A relational database is also known as a relational database management system (RDBMS), or a structured query language (SQL) database. Some of the more well-known relational databases over the years have been Microsoft SQL Server, My SQL, IBM DB2, and Oracle Database.

The non-relational database

Non-relational databases, also known as NoSQL databases, are less structured or confined formats that allow for greater flexibility and adaptability. For example, if you are dealing with a data group that is not clearly defined (not organized or structured) you won’t have the advantage of establishing tables and defined relationships between the data group.

A good example of a non-relational database is Facebook Messenger, because the collected info isn’t structured enough for segmentation into tables. With tons of unstructured information at such a level, it’s stored in a non-relational database. These NoSQL databases are based on data structures like documents, whereby a document can be highly detailed while containing various types of information in different formats.

The advantages and disadvantages of relational and non-relational databases

Now, let’s get down to the nitty-gritty of each database by understanding the pros and cons of each. First, let’s cover the advantages of relational databases.

1. Data redundancy prevention

The tables with the specific data have relations among them, requiring data to be taken from the previous tables, which prevents data redundancy.

2. Data security

RDBMS databases are more secure because access to the data is privileged, meaning that the database administrator has the authority to decide who gets access.

3. Ease of use

This type of database’s tables are better and easier to create and use.

Next, here are a few of the most notable disadvantages of relational databases. 

1. Slower speed

Compared to other databases, the RDBMS databases have a slow extraction of results, which makes it a slower database overall.

2. Memory consumption

Tables having rows and columns consume a lot of physical memory, which can become a disadvantage when it comes to space.

3. Complexity

As the amount of data in a relational database increases, the system becomes more complicated. Each and every piece of data is complex as they are arranged using common characteristics.

Now that the pros and cons of relational databases are more clear, here are the key advantages of non-relational databases. 

1. Flexible data model

Non-relational databases are highly flexible as they are able to store and combine all types of data (both structured and unstructured), whereas relational databases can only store structured data.

2. Evolving data model

Updating the schema of your data model to evolve with changing requirements can be done dynamically, and it will cause no interruption or downtime in your application.

3. High performance

Both throughput (overall performance) and latency (delays between request and response) measure higher in performance in NoSQL databases.

Finally, let’s review some of the top disadvantages of using non-relational databases. 

1. Lack of standardization

NoSQL databases are not controlled by standard rules and functions. These types of databases have a wider variety of designs and query languages than relational databases.

2. Lack of backup solutions

Typically, the tools of NoSQL databases don’t ensure complete data backup solutions. This can cause a problem with backups, but there are some databases like MongoDB that provide more comprehensive tools.

3. Consistency

For NoSQL, scalability and performance are first priorities. However, when it comes to consistency of data, non-relational databases don’t take much consideration of this. This can make them a little insecure compared to relational databases.

What will work best for you?

When it comes to your cloud data storage, there are plenty of decisions to make. But one of the more important ones is whether to opt for relational or non-relational databases—or maybe even both—to meet your unique company needs. Start a free trial of Lytics Cloud Connect today and find out what data management approach may work best for your business.