Articles Cookbook
30 Apr 2023
LearnSQL.com Team

New Monthly SQL Practice for May 2023!

Ready for our new SQL challenge? This time, we have prepared some slightly more difficult SQL tasks. Here’s the May 2023 SQL Practice course! You’ll be helping Sophie, who is running an online document editing app. She would like to gather some data that will help her to expand the business. She hired you as an SQL specialist to help her out. Can you find the average number of documents created by each user?
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28 Apr 2023
Jakub Romanowski

MySQL Crash Course - An Interview With Rick Silva

If you've read my articles before, you probably already know that I love reading. What's more, I also collect SQL books. It may sound weird, but I enjoy comparing different approaches and ways of writing about databases. The best ones end up in our recommended books lists, like The Best SQL Books for 2023. One of those books, MySQL Crash Course, has just been released. I was able to talk to its author, Rick Silva, and this is what he told me.
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27 Apr 2023
Tihomir Babic

How to Use the SQL RANK OVER (PARTITION BY)

Ranking data in SQL is a breeze if you know how to use RANK() to rank over a partition. This article shows you how to do it, as well as how RANK() differs from DENSE_RANK() and ROW_NUMBER(). If you work with SQL in a professional setting, you have had to rank data at least once. Think of ranking months/years/quarters by revenue or costs, best-selling products, most viewed posts or streamed songs, employees by salary, most profitable branches, you name it.
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25 Apr 2023
Alexandre Bruffa

Learn SQL in 10 Minutes

SQL, or Structured Query Language, is a programming language used to communicate with databases. With SQL, you can retrieve data from a database, insert new data, and update or delete existing data. You can even modify the structure of a database: you can add or delete tables or columns and change the relationships between tables. SQL is a standard, meaning it is a reference. Read about the history of the SQL standard in our article “The History of SQL Standards.
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20 Apr 2023
Jill Thornhill

CTE vs. Subquery in SQL: What’s the Difference?

What are Common Table Expressions (CTEs)? Are they the same as subqueries? When would you need to use CTEs? This article looks at the similarities and differences between CTE vs subquery. When I introduce a student to Common Table Expressions, their first reaction is “That’s just a subquery! Why do I need to learn that?”. Let’s answer this question by looking at what you can do with an SQL subquery and what extra advantages there are in using a CTE.
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18 Apr 2023
Tihomir Babic

10 Beginner SQL Practice Exercises With Solutions

Solve these ten SQL practice problems and test where you stand with your SQL knowledge! This article is all about SQL practice. It’s the best way to learn SQL. We show you ten SQL practice exercises where you need to apply essential SQL concepts. If you’re an SQL rookie, no need to worry – these examples are for beginners. Use them as a practice or a way to learn new SQL concepts.
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17 Apr 2023
LearnSQL.com Team

Earth Day 2023

On Earth Day 2023, join hundreds of thousands of people around the world in fighting for the climate. You might be asking yourself ‘wait, why am I reading about this on the LearnSQL.com blog?’ Well, because it's important! Let's take care of our planet, it's our only home! "Invest in our planet." This is the official slogan of this year's Earth Day. We don't know about you, but this sentence motivates us a lot.
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13 Apr 2023
Crystal Frazier

How I Used SQL to Advance in My Career

SQL has become increasingly valuable in today’s job market.  In this article, I will share my personal experience with SQL. I hope it will inspire you to grow in your career and achieve your own goals! A few years ago, I felt stuck in a job that I didn’t fully enjoy. Sure, there were aspects of my job that I appreciated, like building budgets, analyzing the performance of promotional programs, and watching my team grow professionally.
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11 Apr 2023
Nicole Darnley

The Best SQL Blogs to Follow

In this article, you’ll find a list of the best SQL blogs and why they’re worth checking out. SQL (short for Structured Query Language) has been around since the 1970s. It’s still a wildly popular coding language. It is based on the idea that data can be structured and built through relations. If you’re familiar with SQL, you’ve likely heard the term “relational database.” This means that the tables of the database have pre-defined relationships between them: One field in one table will match another field in another table.
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6 Apr 2023
Maria Durkin

Best PostgreSQL Courses for Beginners

So you want to learn PostgreSQL but aren't sure how to get started? In this article, we look at some of the best online courses available on the Internet for learning PostgreSQL, so you can get started right away! What Is PostgreSQL? PostgreSQL is used in major companies such as Apple and Instagram. You may be wondering: should I learn PostgreSQL? PostgreSQL is a popular dialect of SQL, or Structured Query Language, a programming language for accessing and managing data in relational databases.
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