PostgreSQL

  • FAQ
  • Courses
  • Certifications
  • Careers
  • Jobs
  • Companies
  • Skills
  • Articles

What Is PostgreSQL?

PostgreSQL (pronounced post-gress-Q-L) is an open-source relational database management system (RDBMS) that runs on all major operating systems. It offers the full functionality of Structured Query Language (SQL) — a standard programming language for database management — and many other feature enhancements and extensions. PostgreSQL has first-class support for a wide variety of data types, including most standard data types like integer, serial and monetary types, as well as complex types such as arrays, JSON, geospatial and user-defined data types. 

PostgreSQL has transaction support, full-text search and constraints like a foreign key. This RDBMS also has special features intended to help build high-performance systems. Thus, PostgreSQL can scale from one computer to thousands of computers in an enterprise deployment.

More From Abdishakur HassanThe 7 Best Thematic Map Types for Geospatial Data

 

Benefits of PostgreSQL

PostgreSQL is the leading open-source database system and powers thousands of websites, services and applications. It is an ACID-compliant RDBMS. In other words, it offers atomicity, consistency, isolation and durability features. PostgreSQL’s advanced features include stored procedures, triggers, user-defined functions, transactions and replication. 

PostgreSQL provides enterprise-grade scalability performance, availability and functionality. Thus, you can deploy PostgreSQL in a distributed architecture, which can handle large volumes of data. 

Another important feature of PostgreSQL is that it’s open source, which makes it an affordable solution for businesses to keep costs low. Also, PostgreSQL has an excellent track record of reliability and data security. It’s been used in production by customers for decades and is trusted by many organizations and businesses worldwide.

Finally, PostgreSQL has strong compatibility with a wide range of tools and technologies. You can easily integrate it with various applications. It’s also supported by third-party tools, extensions and other programming languages, like Python.

 

How Does PostgreSQL Work?

There are several tools that allow you to interact with PostgreSQL databases. Programmers and advanced users use psql, a terminal-based interactive terminal for PostgreSQL. Yet, for beginners, PgAdmin4, the graphical user interface (GUI), is both a popular and intuitive tool. Both of these tools come with PostgreSQL installation. 

Like most other popular database systems, PostgreSQL is an RDBMS. This means it stores data in tables, where rows represent data items and columns represent attributes of the data items. Data is stored in a row and each row is associated with a unique identifier. When a database table is created, it is associated with a schema that specifies the table’s structure and its relationships. Thus, you can query, select, filter and join tables in PostgreSQL. Database systems like PostgreSQL use indexes to speed up data retrieval. 

Learn PostgreSQL Tutorial. | Video: freeCodeCamp.org

 

PostgreSQL vs. MySQL

Regarding databases, there are no shortage of options on the market. However, many people consider PostgreSQL and MySQL the two most popular relational database management systems available today. The architectural differences between the two databases have an effect on the core capabilities and features they offer. 

PostgreSQL offers more advanced functions, like handling complex queries and advanced data types, while MySQL offers fewer features on advanced functionalities and data types. Thus, setting up and managing MySQL databases is simpler than PostgreSQL. On the other hand, PostgreSQL is ideal for large data sets and large numbers of users when you need feature-rich database management.

 

PostgreSQL Example

Let’s look at an example. This database contains three related tables: student, course and teacher. Each table has a unique column that acts as the primary key for that table. For example, the primary column for the course table is the course_id column. Foreign keys are also important to relate one table to other tables. For example, the course_id column is a foreign key in the student table.

PostgreSQL illustration of related tables and relevant columns
Image: Abdishakur Hassan

When you create your PostgreSQL database and tables, you can query the database using SQL. For example, we can select all students that are part of a course like this in SQL.

SELECT * FROM student WHERE course_id = ‘201B’

 

The output is a list of students that are currently reading the 201B course: Adam White and Joseph Ibrahim. 

 

What Are Alternatives to PostgreSQL? 

PostgreSQL is an enterprise-grade database that provides scalability, performance, availability and functionality. It is open source and is suitable for use cases across industries and use cases. PostgreSQL is the most mature open-source SQL database, and it’s a high-performance, open-source alternative to proprietary databases like Oracle and Microsoft SQL Server. PostgreSQL is also accessible and compatible with many different tools, such as Dbeaver for administration and visualization or QGIS for spatial data connections.

PostgreSQL is well known for its performance, reliability and overall security. As with any technology, however, PostgreSQL is unsuitable for every use case or type of application. It’s best for robust, mission-critical data and large data sets. It may not be suitable for real-time data processing and applications that need real-time data retrieval. Real-time data processing is a distinct business need and often requires specialized tools like Apache Kafka, Amazon Kinesis and StreamSQL.