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Free SQL Course of the Month – PostGIS

What is PostGIS, and why should you learn it? (Hint: Our SQL PostGIS course is free throughout June 2022!)

Did you know databases can store geographic data? This is how interactive maps are made, most often based on PostGIS. In this article, I will tell you what PostGIS is and why it’s worth learning. Moreover, I am going to offer you an awesome online PostGIS SQL course which you can do for free during June 2022!

sql course

How do you get this free PostgreSQL course?

  1. Create a free com account or log in if you already have one.
  2. Start the course. You will have free access to its content until the end of the month.

What is PostGIS?

PostGIS is a geospatial extension for the PostgreSQL database. Honestly, I haven't come across such a good solution in other databases. PostGIS is an add-on, i.e. it’s installed separately from the main PostgreSQL database package. Once you've mastered how to use PostGIS, storing and processing geographic data becomes simple and fun.


You probably remember that databases store different types of data. They can be, among others: numeric, text, date and time, etc. If you would like to know more about it, I recommend the excellent online course Data Types in SQL. You can also read an overview of PostgreSQL data types here.


The main problem with geographic data is its physical size. We are talking about hundreds of terabytes of data. To be able to handle such large data, you need to use a tool that will not clog. PostGIS is ideal for this. It allows you to store and process these large data sets efficiently, and it comes with spatial indices specifically designed to process geographical data.

At this point, it is worth mentioning PostgreSQL itself. PostgreSQL is one of the most popular databases in the world, which makes the ability to use PostgreSQL frequently sought after by employers. Check out Is Learning PostgreSQL in 2022 Worthwhile? for more information. And for some background on this database management system, see Breaking With Filing Cabinets: The History of PostgreSQL.

What Will You Learn in This SQL Course?

Our PostGIS course consists of 148 interactive exercises you can do at your own pace, from anywhere, and at any time. Completing all of them takes about 12 hours.

This online SQL course is divided into eight parts:

  1. Introductory Quiz – Not sure if you're ready to take this awesome course? Take this preliminary quiz to find out. If at any point you get the feeling that it's too difficult, try our SQL Basics in PostgreSQL course first.
  2. Introduction to spatial databases and PostGIS – This is the first step toward working with PostGIS. You will learn the basic terminology related to spatial databases. so you can advance more smoothly into the course’s complex topics.
  3. Geometry basics – This is where the real fun begins. You'll get to know points, linestrings, and polygons.
  4. Relationships between geometries – How can points, linestrings, and polygons relate to each other? In this part of the course, you’ll find out.
  5. Additional geometry features – In this part, we'll present further spatial functions and introduce collections.
  6. Geography – This is where you’ll learn to work with the geography column type. Don't be afraid; it's really cool!
  7. Practice – This section has some additional exercises so you can put into practice everything you have learned so far. Because practice makes perfect!
  8. Final quiz – At the end of the course, there’s a final test for your skills. It is quite difficult, but don't worry! If you put the effort into learning PostGIS and did all the exercises carefully, you’ll do fine!

To make your learning process more interesting, we'll be working with both real and not-so-real places in San Francisco and the United States. Additionally, we've prepared a special surprise – some exercises will even let you see the results of your queries drawn on a real-world map!

I mentioned earlier that this course is interactive, like all SQL courses at You’ll learn PostGIS as you’ll use it in the real world,  writing real SQL queries and solving real problems. Everything happens in our online console, where you will write code and watch its results. If you make a mistake somewhere, you’ll immediately see what you need to work on. And you can use hints for more difficult tasks. All you need is an Internet connection and your favorite browser.

sql course

You won't find any time-wasting fluff in our online SQL courses. We give you the necessary knowledge and a chance to test it in practice.If you want to know more about our online SQL courses and how we develop them, read the Behind the Scenes at How Our SQL Courses Are Created.

Learning SQL has never been easier. If you are looking for good advice on how to learn SQL more efficiently and have some fun at the same time, check out these articles:

Do you want to learn even more about PostgreSQL? This SQL course is part of our SQL from A to Z in the PostgreSQL track. There, you’ll find everything you need to become a PostgreSQL expert! Check it out!

Who Should Take This Course?

We created this PostGIS course for database users who need to develop their skills in working with spatial and geographic data. The SQL course is also useful for students during their computer science and database classes.

Maybe you are a programmer and you are currently working on an application that uses spatial data – e.g. for easier parking in the city, showing new bicycle paths, or finding the nearest vegan restaurants? Then PostGIS should be included in your skillset.

sql course

After completing this online SQL course, you’ll receive a PDF certificate. You can publish it on your LinkedIn profile. Check out how easy it is to do so in our short guide.

Employers are looking for people who can work with PostGIS. Maybe this is an idea for a new career? If so, start looking for job opportunities on one of these sites. And if you find your dream job, you should prepare yourself well for the interview. These articles will help you:

Free SQL Course for June: PostGIS

Have you felt like learning PostGIS? Great, remember that you can learn it for free until the end of June 2022. Yes, you read that right! This great online interactive PostGIS course is free. It is our SQL course of the month. We give you free access to all exercises.

Seriously, there is no catch here. Just log in and learn PostGIS!

Happy learning!