Ways to Learn SQL

Last week at The Data School in Sydney, we learned basic and intermediate SQL querying. Like most skills that we have learned about so far, we approached different facets of SQL in a formulaic way:

• Explanation of [SQL concept here]
• Demonstration of [SQL concept here]
• Practice question(s) of [SQL concept here]
• Repeat with [next SQL concept here]

I used to be a mathematics teacher, and this way of learning felt a lot like a typical lesson. I want to emphasize that learning this way isn’t inherently flawed, but it does have its limitations. Over time, this method can become extremely dry—even for highly motivated learners. Many of us in The Data School felt exhausted after working through different types of clauses, joins, subqueries, and more.

But then something changed.

We were given an activity called SQL Murder Mystery, and suddenly, we were hyper-focused and engaged. It reminded me of the lessons I used to plan for my students—and why I put in the effort to make them engaging. Sometimes, learning (and the motivation to learn) is best achieved through a mix of strategies… and SQL is no different.

So, here’s a short list of ways you can learn SQL on your own—and as a bonus, all of them are free!

TLDR: This blog is going to be a list of ways you can learn SQL.

 

1) YouTube

SQL tutorials on YouTube are in surplus; from video playlists to multi-hour-long crash courses, many channels offer the knowledge to take viewers from “SQL zero to SQL hero”. YouTube can be an excellent place to build foundational knowledge. However, I recommend learners avoid only watching videos as this process is extremely passive. Whilst visual and auditory learning methods (i.e., videos) can significantly benefit knowledge retention (Liu & Lahoz, 2024), listening to an expert can only take someone so far. Learners must actively construct knowledge in their own minds by discovering and transforming information (Bada & Olusegun, 2015). Basically, “doing” beats “listening”. Does this mean you shouldn’t use YouTube? No. Just use it smartly.

Some channels like Alex The Analyst encourage viewers to follow along with their videos. This is close to the best of all worlds assuming viewers actually take the time to pause and practice. In the video below, Alex even starts by showing viewers how to download an RDBMS (Relational Database Management System) called MySQL Server, an excellent starting point before any of the actual SQL queries.

 

2) HackerRank

HackerRank is a solid tool for beginner and intermediate SQL learners. HackerRank gets users to write and test SQL queries in their web browser, so installing an RDBMS is unnecessary. This tool is mostly challenged-focused as opposed to tutorial-based, so there are assumptions made about users’ familiarity. Therefore, it may be best for absolute beginners to pair HackerRank’s challenges with online resources like tutorials from YouTube or Khan Academy.

I like the subtle gamification HackerRank implements, as each completed challenge earns the user points, leading to badges that demonstrate their proficiency. Whilst the challenges themselves aren’t always very practical, there is benefit in being tested on a wide array of concepts in unfamiliar ways. This gets users to deepen their knowledge by stopping to think about how certain queries work.

 

 

Moreover, users can attain three SQL certifications in HackerRank which can be used to demonstrate your skills when job hunting (or simply make for a nice LinkedIn post). These certifications are also free!

 

 

3) SQL Squid Game (and DataLemur)

I know right… SQL Squid Game? That sounds awesome. Like HackerRank, but in a more entertaining way, SQL Squid Game gamifies the practice of SQL. Users play the role of a data scientist hired by the Squid Game organisation and query player data for The Front Man across 9 levels that progress in difficulty. The written story of the game is very witty and highly entertaining, making for an engaging experience. In saying that, I don’t think it’s an ideal way to learn SQL.

If you’re an intermediate learner, or even a beginner with some knowledge, SQL Squid game could be a great consolidation tool to practice queries in unfamiliar situations. An absolute beginner would likely struggle, even with the optional hints provided at the bottom of each level (although, these optional hints are an excellent feature that HackerRank does not have).

SQL Squid Game is owned and operated by the DataLemur website. DataLemur has a broad range of interactive tutorials designed to cover beginner to advanced SQL topics, effectively allowing a user to learn from scratch. These tutorials are embedded into the SQL Squid Game’s optional hints, meaning users can help themselves when they’re stuck. Furthermore, the layout of tutorials is extremely easy to navigate, making the whole website very user-friendly and well-integrated.

 

 

Final Piece of Advice

This may sound obvious, but to get better at SQL you need to practice SQL. Like anything you have ever improved at, you probably did so with practice, and this is the same. I suppose this can be easy to forget at times, so here is a picture that might make it easier to remember:

The forgetting curve is a real theory with strong implications for learning. If you want to remember SQL a week, a month, or even a year from today, you’ll need to keep practicing. You might as well make it as fun and as easy as possible by using the resources discussed in this blog. Thanks for reading!