Articles Cookbook
19 Jan 2023
Tihomir Babic

What Is a CTE in SQL Server?

What is a CTE, and how do you write a CTE in SQL Server? Join us on a journey where we’ll see all the typical usage of a CTE in SQL Server. CTEs (or Common Table Expressions) are an SQL feature used for defining a temporary named result. You can think of it as a temporary table whose output is available only when the main query is run. This is practical because the CTEs result isn’t stored anywhere but can always be referenced inside the query like any other table.
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17 Jan 2023
Jill Thornhill

Is SQL Hard to Learn?

If you have no IT skills, how hard is it to learn SQL? Will it be too technical for you? Is it worth the effort? And where would you start? In this  article I will answer those questions. As an IT consultant and trainer, I've often advised people to learn SQL. And, almost as often the reply has been, "Is it hard to learn SQL? Do I need technical or IT skills to learn it?
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12 Jan 2023
Tihomir Babic

How to Practice SQL Window Functions Online

Learn and practice SQL window functions from the comfort of your home! Here’s how to do it. The last few years have shown that working from home has many benefits over the daily  commute. No wonder people are reluctant to go back to the office! They have much more time while doing the same work. What do you do with the extra time? Whatever you want. It’s your time!
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10 Jan 2023
Alexandre Bruffa

Database Jobs to Choose in 2023

In this article, we will explore some of the top database jobs to choose from in 2023. So you want to land yourself a database job in 2023. It’s a great choice, and there are lots of options. Let’s talk about the most popular data-related jobs and what you need to do to get one. SQL Is Essential for a Database Job It’s important to mention that most of the popular databases nowadays are relational – i.
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6 Jan 2023
Jakub Romanowski

Free SQL Course of the Month – Window Functions in PostgreSQL

Are you looking for the best way to master SQL window functions? In this article, I'll show you how you can do so for free. Throughout January 2023, you can access the interactive course Window Functions in PostgreSQL for free. Hurry, time is running out! Need a free PostgreSQL course on window functions? You've come to the right place! If you are reading this article, you probably know PostgreSQL is one of the most popular databases in the world.
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5 Jan 2023
Nicole Darnley

UNION and UNION ALL in SQL: What They Do and How They’re Different

In this article, we’ll explore the SQL clauses UNION and UNION ALL. Learn what they do and when to use each one. I had been an analyst for probably four years before I knew about the SQL clause UNION ALL. I used UNION on a regular basis, but had never heard of its counterpart. Then one day when I heard a coworker talking about it. I thought to myself, “What is he talking about?
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3 Jan 2023
Kamila Ostrowska

SQL Books for Beginners

How can you learn SQL more efficiently? Besides a good online course, find an interesting book to enrich your knowledge. Here are the best SQL books for beginners. SQL, or Structured Query Language, is a very powerful tool to work with many types of data. If you are interested in learning SQL you probably know how useful it is, and how widely it is needed. To learn SQL successfully, a solid online course for beginners like our SQL Basics is a great start.
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1 Jan 2023
LearnSQL.com Team

New Monthly SQL Practice for January 2023!

Ready for our new SQL challenge? This time, we have prepared slightly more difficult SQL tasks. Here's the January SQL Practice course! This SQL Practice is at an advanced level and is aimed at those who have finished our SQL Basics and Window Functions course or otherwise have the equivalent knowledge. If you do not feel comfortable working with SQL window functions yet, make sure to check out these courses first and then come back here for more practice.
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29 Dec 2022
Ignacio L. Bisso

How to Practice SQL Subqueries

Have you ever wondered what separates beginners from advanced SQL users? It includes things like, for example, subqueries. In this article, I explain their importance and why you need to practice SQL subqueries to become an expert. What Is an SQL Subquery? SQL is an easy-to-learn language. However, there are certain complex features and techniques of the language that require practice. One of these features is the subquery, which adds great expressive power to the language and your projects.
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27 Dec 2022
Alexandre Bruffa

Learn Advanced SQL with LearnSQL.com

In this article, we will propose a learning path that will cover advanced SQL topics. If you already know the basics of SQL, you probably have figured out that most online and offline SQL tutorials and courses usually cover the basic and intermediate concepts: SELECT, FROM, WHERE, ORDER BY, GROUP BY, and joining tables. Even university database courses typically don’t cover more advanced  SQL topics. While this is enough SQL for most everyday tasks, there are some relatively new features that have been added to SQL in the last 20 years: window functions, recursive queries, and GROUP BY extensions (ROLLUP, CUBE, GROUPING SET).
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