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New SQL Course: GROUP BY Extensions in PostgreSQL

Do you want to take your knowledge of PostgreSQL to the next level? I have something for you:’s new GROUP BY Extensions in PostgreSQL course! It will help you get even more out of your data and create better reports and summaries. Fasten your seat belts and prepare to see what GROUP BY can do when it’s turbocharged.

First, I have to confess something. I am not objective – I think PostgreSQL is the best and coolest SQL dialect. I started learning with SQL Standard, but I do projects and data analysis on a daily basis in PostgreSQL. Why? Because it’s very effective and allows for efficient and trouble-free work. If you don’t believe me, read my article about which major companies use PostgreSQL and what they use it for. Who wouldn't like to be like Spotify, Skype, or NASA?

What Are GROUP BY Extensions?

Let's start with what the GROUP BY clause is. Essentially, it helps you group the data that results from your queries. GROUP BY is useful when you need to do statistical calculations for individual groups or when you need to narrow the results. I'll give you a real-world example.

Imagine you are the owner of a thriving online store that sells t-shirts. Thanks to the GROUP BY function, you can calculate the average order value for individual customers or find out how many customers you have in a given city. Cool, right? Such information is necessary when planning orders and deliveries (and for lots of other things, as well).

GROUP BY is one of the basic reporting tools in PostgreSQL. Therefore, it’s good to know this function and be able to apply it effectively. That is why I recommend you check out this article on how GROUP BY works. You can also read a simple explanation of the difference between GROUP BY and ORDER BY.

Now that you know what GROUP BY is, we can move on to the main course of this meal – GROUP BY extensions. In our interactive GROUP BY extensions in SQL course, you will learn ROLLUP, CUBE, and GROUPING SETS. They will allow you to extend the normal function of GROUP BY, performing multiple groupings with just one SQL query. They also help you prepare SQL reports more precisely. Bon appetit!

GROUP BY Extensions in PostgreSQL Course

What will you find inside this course? Lots of exciting things. As mentioned earlier, you'll learn how to use ROLLUP, CUBE, and GROUPING SETS operations in PostgreSQL. What do each of these do?

Learn GROUP BY Extensions in PostgreSQL

ROLLUP lets you present subtotals along with the total sum. These are often called super-aggregated rows. This function is great if you want to generate multiple grouping sets using just one SQL query.

What if you want to generate subtotals? Nothing is easier when you master the CUBE extension. If you use it in your SQL query, you can get subtotals for all combinations of the grouping columns specified in the GROUP BY clause.

GROUPING SETS is a step further, as it allows for computing multiple GROUP BY clauses in a single SQL statement. GROUP BY GROUPING SETS is equivalent to the UNION of two or more GROUP BY operations in the same result set.

You’ll get more than theory in our interactive course; you’ll be able to practice what you’ve learned right away. You will write PostgreSQL queries directly in our console. You don't need to install or set anything up; everything is in the browser. Just log into your LearnSQL account and you can learn right away.

GROUP BY Extensions in PostgreSQL contains 63 great interactive exercises. You can learn at your own pace, anywhere, and at any time. Completing all the parts should take about 7 hours. Of course, no one can do it all at once. It will probably take a week to complete the whole thing.

This course is part of our SQL from A to Z in PostgreSQL track. This is a complete PostgreSQL learning path for beginners. It contains a comprehensive set of courses that allow newcomers to learn all the features used in modern SQL. If you're serious about working with PostgreSQL, this track, filled to the brim with great exercises, will be perfect for you.

Who Should Learn GROUP BY Extensions in PostgreSQL?

We have created this course primarily for analysts who frequently use PostgreSQL to create reports and summaries. We wanted to give them better tools to use on their everyday challenges – tools to make their work easier and more effective.

PostgreSQL database administrators and students taking classes in PostgreSQL will surely benefit from the course. It’s also good for developers who use PostgreSQL databases and want to enhance their SQL skills. And if you’re looking for a SQL job, you can display the certificate of completion for this course on your LinkedIn profile.

Learn GROUP BY Extensions in PostgreSQL

If you are an entrepreneur and databases are just one of your money-making tools, consider learning PostgreSQL. Start with SQL Basics in PostgreSQL and then return to GROUP BY to make better strategic decisions for your business. You may also find the Creating Basic SQL Reports in PostgreSQL course useful.

Will You Learn PostgreSQL’s GROUP BY Extensions?

I hope I’ve convinced you to learn the great GROUP BY extensions that PostgreSQL offers. If you’re still wondering if it is a good idea to follow the PostgreSQL path, see my list of the most popular databases and decide for yourself whether it’s worth betting on PostgreSQL.

If you want to learn PostgreSQL, don’t be alarmed by the setup process; you can easily install it on your home computer and start working on your own projects. Our article How to Install PostgreSQL on Windows 10 in 5 Minutes will walk you through it. Whatever you use relational databases for, PostgreSQL is the answer!