SQL Course of the Month – SQL Practice Set

It is said that practice makes perfect. I agree with this statement one hundred percent. What is applicable in basketball training, playing an instrument, or learning a foreign language is also useful in learning SQL. Practicing writing queries, using functions, and putting together clauses is the basis for learning the true power of SQL. But how and where do you practice SQL? I spoke with Agnieszka Kozubek-Krycuń, Chief Content Officer at Vertabelo about this. She knows SQL better than just about anyone and is probably the best person to ask about practicing SQL. Her answer was the SQL Practice Set course.

What Does It Mean to Practice SQL? What Is the Best Method for This?

The best method for practicing SQL is to actually write SQL queries, run them against a database, and verify if they return what you expect them to return. This way, you have to remember the syntax of SQL, recall (or find on the Internet) the name of the function you want to use and its arguments, and fix any typos or other mistakes you make.

This is how you use SQL in real life, and this is how you should practice it. After all, it is possible to write a query that will run without syntax errors but will not return what you wanted. Spotting mistakes is a skill that can only be practiced by running your queries on a real database.

You Have Many Years of Experience in Teaching Computer Science Academically. From a Scientist's Point of View, How Important is Practice for Acquiring Knowledge?

It’s very important. In my opinion, by practicing SQL or any other skill, you are able to learn it well.

Research shows that recall, trying to remember what you learned, is a more effective learning method than rereading a section in a textbook for the hundredth time. When you learn something new, you should read a section in a textbook or watch a lecture and then try to make your own summary of it. This way, you force your brain to revisit what you learned one more time and remember the new concepts better.

Practice does the same thing: it forces you to find in memory the details, the syntax, and the concepts and apply them to create a solution. That’s why it’s important to actually write the SQL query. Don’t just look at a problem and think, “I know how to do it.”

Maybe the problem has a hidden catch that you haven’t noticed at first glance. Just try to write the solution on your own. You might get stuck more often than you expect. I know I do.

If you’re interested in the science behind recall and tips on effective learning, I recommend a very good (and free!) course, “Learning How to Learn,” on Coursera and a book, “A Mind For Numbers,” by Barbara Oakley, one of the creators of the Coursera course.

There Are Many Places Where You Can Write SQL Queries. Why Choose the SQL Practice Set Course?

With our SQL Practice Set course, all you need is a web browser and an internet connection. You don’t need to install anything on your computer. We have prepared a set of exercises focused on the most common problems beginners face. You don’t need to look for a data set, install a database, or search for good SQL exercises.

Our course is a one-stop-shop to practice SQL. You type a query in the browser and run the query, and our platform tells you if your solution is correct or not.

What Topics Does This Course Cover? What Will I Practice?

There are 88 interactive exercises in this course, divided into five parts. Each part starts with a very brief review of the topic covered and then proceeds to the exercises. The topics covered in the course are selecting from one table (practicing the WHERE clause), aggregation, grouping (GROUP BY), JOINs, and subqueries.

We end the course with a challenge: a set of exercises that force you to combine the knowledge from all previous parts. This is a good course to review your SQL knowledge or to identify problem areas that you need to work on.

Is the SQL Practice Set Part of Some Larger Track?

The SQL Practice Set course is part of our SQL Practice track. We created the track for users who know the basics of SQL (e.g., they’ve completed our SQL Basics course) and would like to practice writing SQL queries. The track focuses on topics that are challenging for beginners. There are two courses in the track: SQL JOINs and SQL Practice Set.

Who Should Take This Course?

I recommend this course to people who would like to consolidate their knowledge of SQL. This course is ideal for students preparing for an SQL exam, jobseekers preparing for an interview that requires SQL, or anyone who wants to refresh their SQL knowledge.

Many People Say This Course Is Great When You Are Preparing for an Interview for a Job Requiring SQL. What Do You Think?

This course is a great resource for anyone who wants to refresh their knowledge of SQL, including before an interview. Are you one of these people? Great, take our course, and see what interview questions you may encounter in our article “Complete SQL Practice for Interviews.” Also, read “What SQL Practice Do You Need to Prepare for a Technical Job Interview.”

At the End of Other LearnSQL.com Courses, I Received a Certificate That I Could Post on My LinkedIn Profile. Will I Get One for This Course?

Of course. As soon as you finish all of the exercises, you will get a certificate. We encourage our users to attach such certificates to their CVs and LinkedIn profiles.

It is also worth showing off your new skills on social media. You never know, maybe your boss will see it and give you a raise. Or maybe some recruiters will notice you and call you with an interesting offer.

You Are Chief Content Officer at Vertabelo. This Means That You Either Co-Authored or Supervised the Creation of All Courses on the LearnSQL.com Platform. Do You Remember Your Work on This Course?

After we released our SQL Basics course, we realized that for some users, the basics course is not enough. They wanted more practice, and they needed more time to consolidate their knowledge of SQL. That’s how we got the idea to create a practice set for SQL.

We identified a set of topics that beginners often find challenging: JOINs, aggregation, grouping, and subqueries. We also decided on a course formula different from “SQL Basics.”

We wanted a course that forces you to recall your SQL knowledge. So, each course part starts with a brief review of the topics and a set of exercises. And that’s how we arrived at the “SQL Practice Set”.