On the Internet you can find a huge number of various database ratings. However, not all of them are based on in-depth market research. As a rule, most ratings are based on the number of servers for each database or companies using each database. We decided to take as a basis the Stackoverflow rating where more than 90,000 developers that use databases were surveyed around the world. This rating can be considered an assessment of the demand for each database as a solution in applications development.

So, we're on a mission to break down the top 5 most popular databases. Why are they our go-to choices? What makes them stand out? Let's dig in and find out together.

PostgreSQL

PostgreSQL is an object-relational database management system (ORDBMS), one of the most advanced open DBMS in the world. It is an open source alternative to commercial databases.

Early versions of the system were based on the old POSTGRES University program created by the University of Berkeley: this is how the name PostgreSQL came to life. And now the DBMS is sometimes called “Postgres”.

One of the main reasons for the PostgreSQL database is its versatility. The database is suitable for most operating systems, including Windows, Linux, Macos and Unix. Due to the fact that the database is open source, it is easy to improve it, define your own data types, create new functions, and even write code in another programming language without recompiling the database.

As a matter of fact, it is not a surprise that PostgreSQL ranks first in the rating. Below is a list of main beneficial characteristics of PostgreSQL that helped it win this “popularity race”:

• Robust feature set. PostgreSQL is one of the most sophisticated databases with a huge range of features to improve performance, improve security, a set of extensions and other settings. Robust authentication, access control, and enhanced security, privilege management systems - all these features are beneficial for organizations of any size. PostgreSQL supports views and materialized views, foreign data wrappers and even supports No-SQL behavior such as storing documents using JSONB. You can see in more detail how powerful PostgreSQL is in a detailed comparison.

• ACID compliance. ACID is a term in computer science that refers to atomicity, consistency, isolation, and durability. Basically, it is a set of properties of database transactions intended to guarantee data validity despite errors and power failures. ACID compliance is a primary concern for relational databases as it represents the typical expectations for storing and modifying highly structured data. While other relational databases still intend to provide ACID compliance, PostgreSQL has had ACID-compliance since 2001. As a comparison, MySQL only ensures full ACID compliance when using their InnoDB or NDB database engines, which can lead to unexpected corruption if other engines are used.
• Multiple data types. Another feature of PostgreSQL is its support for a large number of types of information. Among them there are numeric data type, character data type, date/time data type, Geometric type, Boolean data type, Monetary type, Binary data type, Network type, UUID type, Enumerated type, and many others. This diversity allows users to efficiently store and manipulate diverse data types and accurately model complex data structures and tailor database schemas to suit specific application requirements. In addition to such a large arsenal, the database also allows you to define your own data types. If necessary, the DBMS allows to support the data types that are needed in a specific project. PostgreSQL has several internal formats that are used only within it.

As PostgreSQL continues to gain widespread popularity, many companies are transitioning their systems to it. Another reason for that -  they save a great deal on total cost of ownership (TCO). The reliability and ease of management of  PostgreSQL can save the money and time spent on troubleshooting and fixing downtime and performance issues. Companies often prefer PostgreSQL over other solutions, such as Oracle (News - Alert), and migrate Oracle to PostgreSQL.

MySQL

MySQL is one of the most popular open source databases in the world. With its proven performance, reliability and ease-of-use, MySQL has become the leading database choice for web-based applications, covering the entire range from personal projects and websites, via e-commerce and information services, all the way to high profile web properties including Facebook, Twitter (News - Alert), YouTube, Yahoo! and many more.

What makes MySQL so popular? MySQL is one of many RDBMSs available in the market. Still, it is among the most popular ones — second only to Oracle Database when compared using critical parameters like search engine results, LinkedIn (News - Alert) profiles, and frequency of mentions on online forums. In addition, the reliance of major tech giants on MySQL further solidifies its popularity.

Why is MySQL so popular? It is hard to provide a definite answer. However, it is possible to highlight the most vivid characteristics that make MySQL stay in the spotlight:

• MySQL is easy to use.  MySQL is widely known for its user-friendly interface, appealing to both novice users and seasoned developers alike. With its intuitive design, MySQL minimizes the learning curve, making it accessible to beginners while still offering advanced features for experienced users. Its similarities to other relational databases facilitate a smooth transition for junior developers familiar with alternative systems, further enhancing its usability and reducing barriers to adoption.

In addition, MySQL is open source, so it doesn’t require a money bag to start using it compared to enterprise databases. The exception is only an advanced version which requires purchasing for the most comprehensive set of advanced features, management tools and technical support to achieve the highest levels of MySQL scalability, security, reliability, and uptime.

• MySQL is secure. Many companies restrain themselves from using open-source software considering such databases less secure than the commercial ones. However, MySQL provides exceptional security and data protection capabilities. It prioritizes data security with its access privilege system and user account management. MySQL is used in many web applications, such as Twitter and Facebook (News - Alert), and CMS such as Joomla, Drupal, and WordPress. For transactional processing, data support and security might be beneficial to your organization, particularly if you work in the e-commerce industry.
• MySQL is highly efficient. MySQL offers a unique storage engine that allows easy administration of the database. One of the hallmark features of it is that it allows configuring the MySQL database server to achieve peak performance. In other words, even in times of peak traffic on your website, your database will withstand high loads.

MySQL, like PostgreSQL, offers ACID compliance, ensuring that transactions are executed reliably and consistently. With features like transactional rollback and commit, developers can confidently manage complex operations involving multiple database changes. What is more, with features such as complete atomic, durable transaction support and multi-version transaction support it is the perfect solution for full data integrity. It guarantees instant deadlock identification through server-enforced referential integrity.

SQLite

SQLite is an embedded, server-less relational database management system. In fact, it is an in-memory open-source library with zero configuration and does not require any installation. Also, it is very convenient as it’s less than 500kb in size, which is significantly lesser than other database management systems.

Compared to the previous “titans” SQLite has to be a special one to compete with them. It is indeed a special database that is quite different from the other databases reviewed in this article. Here are the most interesting and distinctive features of SQLite:

- Serverless. Usually, a database system like MySQL or PostgreSQL needs a separate server process to work. Applications wishing to connect to the database server employ the TCP/IP protocol to transmit and receive requests. This is referred to as client/server architecture. SQLite does not work like that. The SQLite database is incorporated with the application that utilizes the database. The applications engage with the SQLite database by directly reading and writing from the database files saved on the disk.

- Self-contained. SQLite is self-contained, meaning it requires minimal support from the operating system or external library. This enables SQLite to be functional in all settings, particularly in embedded systems such as iPhones, Android (News - Alert) phones, gaming consoles, portable media players, and so on.

- Zero-configuration. Because of the serverless architecture, you don’t need to “install” SQLite before using it. There is no server process that needs to be configured, started, and stopped. In addition, SQLite does not use any configuration files.

- Transactional. All transactions in SQLite are fully ACID-compliant. This implies that every query and modification is Atomic, Consistent, Isolated, and Durable. In a transaction, changes are either completed entirely or not done at all. This applies even in the presence of unexpected issues such as a crash, power loss, or system failure.

This database serves the best solution for various use cases in situations where simplicity of administration, implementation, and maintenance are more important than the countless complex features that enterprise database engines provide.

MongoDB

What is MongoDB? MongoDB is a database based on a non-relational document model. Thus, as a so-called NoSQL database, it differs fundamentally from conventional relational databases such as Oracle, MySQL or the Microsoft SQL Server. The name MongoDB is derived from the English word “humongous”, which roughly means “gigantic”.

Let’s review some of the salient MongoDB features:

• Each database contains collections which in turn contain documents. Each document can be different with a varying number of fields. The size and content of each document can differ from each other.
• The document structure is more in line with how developers construct their classes and objects in their respective programming languages. Developers will often say that their classes are not rows and columns but have a clear structure with key-value pairs.
• The rows (or documents as called in MongoDB) don't need to have a schema defined beforehand. Instead, the fields can be created on the fly.
• The data model available within MongoDB allows you to represent hierarchical relationships, to store arrays, and other more complex structures more easily.
• Scalability. The MongoDB environments are very scalable. Companies across the world have defined clusters with some of them running 100+ nodes with millions of documents within the database.

If No-SQL is a king, then MongoDB is a crown. The reasons for that are numerous. NoSQL databases have grown in popularity over the last decade because they allow users to query their data without having to learn and master SQL. What is more, a mature ecosystem of tools, document validations, the sharding and aggregation framework are one of the main reasons for MongoDB becoming the most popular document-oriented database.

Microsoft SQL Server

Microsoft SQL Server is a database that doesn’t need an introduction. It is an enterprise database management system widely known all over the world. SQL Server uses Transact-SQL (T-SQL), a proprietary language of Microsoft that has the ability to handle exceptions, declare a variable, and manage stored procedures.

The SQL Server Database Engine, the central component of SQL Server, is in charge of controlling, processing, and safeguarding data storage. The database engine is split into two parts: the relational engine, which processes commands and queries, and the storage engine, which is responsible for managing various database elements like tables, pages, files, indexes, and transactions.

This database is well known all around the world for decades. It boasts a set of advantages that make it a reliable solution. Some may argue, but it is possible to enumerate its advantages for hours. Let’s find out the most vivid benefits of Microsoft SQL Server:

- Improved efficiency. SQL server boasts built-in features for transparent data compression and encryption, leading to superior performance. Users don't need to alter programs to encrypt and secure data. SQL Server offers effective permission management tools and access controls, designed to protect sensitive business data.

- Exceptional Security. The SQL Server database is exceptionally secure, employing advanced encryption algorithms that make breaching the security layers virtually impossible. SQL Server is a commercial relational database equipped with extra security features to mitigate the risk of attacks.

- Reduced ownership cost. SQL server's efficient data mining, disk partitioning, and data management tools aid in preserving vital data and freeing up storage space for highly sensitive information.

Besides the fact that the database itself is very powerful without obvious weaknesses, Microsoft also promotes it through bundling it with its other products.

Although SQL Server is an excellent database with many advantages, some companies still prefer the open-source PostgreSQL database. It's not easy to pinpoint the exact reasons for this choice, but it's possible that companies switching from SQL Server to PostgreSQL want to avoid getting too tied to a specific vendor.

Conclusion

To conclude, choosing the right database for your needs is, undoubtedly, an important decision for information management. Each of the five popular databases we examined - PostgreSQL, MySQL, SQLite, MongoDB, and Microsoft SQL Server - brings its unique strengths to the table. Whether you prioritize flexibility, scalability, or transactional integrity, there's a database solution out there for you.

Remember, the best choice depends on your specific requirements, budget, and the nature of your data. MySQL simplicity might appeal to startups on a tight budget, while MongoDB document-oriented approach could be a game-changer for those dealing with diverse and unstructured data.

Ultimately, staying informed about the latest developments in the database landscape is key to making informed decisions that will benefit your organization in the long run. Keep exploring, testing, and adapting to ensure that your data management strategy aligns seamlessly with your evolving business needs.