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Monthly SQL Challenges in 2021

by Agnieszka Kozubek-Krycuń

14 Jan 2021 Did you know that LearnSQL.com provides a monthly SQL Challenge? Every month, we publish a new set of SQL practice exercises. Find out what to expect from our SQL challenges in 2021. Here at LearnSQL.com, we believe that the best way to learn SQL is through practice. After all, writing SQL is a practical skill. That’s why all our SQL courses (and there are over 30 of them!) are interactive: You learn SQL by writing SQL code.

What’s the Difference Between SQL CTEs and Views?

by Kateryna Koidan

14 Jan 2021 SQL views vs. CTEs: What do they do? How are they different? Which one should you use and when? Get your answers here! In SQL, both CTEs (common table expressions) and views help organize your queries, leading to cleaner and easier-to-follow code. However, there are some important differences between them. This article will walk you through several examples of CTEs and views and explain when to use each one.

What Is LEFT JOIN in SQL?

by Kateryna Koidan

13 Jan 2021 Get to know the details of LEFT JOIN, one of the most common SQL JOIN types. SQL is mainly about getting data from databases. Very often, you’ll need data to be combined from multiple tables in your database. That’s when JOINs come into play. LEFT JOIN is one of the JOIN types that you are likely to use very often. In this article, I’ll explain the syntax of LEFT JOIN and how it works using several examples and illustrations.

Best SQL Video Tutorials for 2021

by Jakub Romanowski

12 Jan 2021 Ready for this year’s picks for the best YouTube SQL video tutorials? Here are our top 5 choices! It's been well over a year since I last wrote about SQL tutorials on YouTube. Those seven channels can help you learn the basics of SQL quite painlessly, but now it's time to add to that list with 2021’s top contenders. Which YouTube SQL tutorials are worth your time and attention? I’ve got my favorites, but first, let’s consider an important question:

What Is Auto-Increment in SQL?

by Martyna Sławińska

8 Jan 2021 In this article, we’ll learn the basics of the auto-increment feature of SQL: what it is and how to use it efficiently. One of the many features offered by SQL is auto-increment. It allows us to automatically generate values in a numeric column upon row insertion. You could think of it as an automatically supplied default value – the next number in a number sequence – that’s generated when the row is inserted.

An Overview of Aggregate Functions in SQL

by Tihomir Babic

7 Jan 2021 Aggregate functions are commonly used in SQL. This article will lead you through their use and show examples of how they work. SQL aggregate functions are a useful tool, especially for creating reports. They’re not difficult to understand, especially if you have some experience with Excel or similar programs. You’ve probably used aggregate functions like SUM or AVERAGE in a spreadsheet. Even if you only occasionally use them, knowing aggregate functions can help you better understand your data and work more efficiently.

LearnSQL Track of the Season: Creating Database Structure

by LearnSQL.com Team

6 Jan 2021 New year, new challenges, and ... a new SQL Track of the Season! Start 2021 by learning SQL and data engineering. In this article, we answer frequently asked questions about our Creating Database Structure track. Maybe you haven't noticed yet that there’s an order to many LearnSQL.com courses; you can learn SQL by doing them in the right order. We call this option our ‘SQL tracks’. These are logically structured and well-thought-out learning paths that will help you take the next steps towards becoming an SQL expert.

SQL Course of the Month – Standard SQL Functions

by LearnSQL.com Team

5 Jan 2021 Are you dreaming of becoming a data analyst? Or maybe you just want to work effectively with your company’s databases? You can – with SQL functions. We’ve selected Standard SQL Functions to be our January 2021 SQL Course of the Month. What will you find inside? I asked Agnieszka Kozubek-Krycuń, Vertabelo's Chief Content Officer, about it. Here's what she said. What are SQL functions? The term reminds me of SELECT or JOIN.

New Monthly Challenge for January 2021!

by LearnSQL.com Team

1 Jan 2021 This month’s LearnSQL.com Monthly Challenge is now available! In January, you can test your SQL skills in window functions by solving problems for Jeremy, the manager of the clothing retailer, Edward. Is this the first time you’ve come across our Monthly Challenge? LearnSQL.com delivers one SQL Challenge each month to our users. Starting in January 2021, we have monthly challenges separately for beginners and for advanced users. Each challenge contains 5 to 10 SQL exercises, prepared for those who want to practice their skills.

SQL JOIN Tips for Beginners

by Tihomir Babic

1 Jan 2021 If you’re a beginner and want to know how to start using SQL JOINs in your queries, you’ve come to the right place. Using the SQL JOIN clause is necessary if you want to query multiple tables. Sooner or later, you’ll have to use more than one table in a query. It’s the nature of relational databases in general – they consist of data that’s usually saved in multiple tables; in turn, these form a database.

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