Articles Cookbook
18 Dec 2023
Ignacio L. Bisso

Can You Use Multiple WITH Statements in SQL?

A comprehensive guide to multiple WITH statements in SQL, perfect for beginners and experts alike. The SQL WITH clause allows you to define a CTE (common table expression). A CTE is like a table that is populated during query execution. You can use multiple WITH statements in one SQL query to define multiple CTEs. In this article, we will explain how to define multiple CTEs in a single query.
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12 Dec 2023
Martyna Sławińska

SQL Subquery Practice: 15 Exercises with Solutions

Subqueries are often challenging for beginners. Practice makes perfect, so join us as we work through these 15 SQL subquery practice exercises! In SQL, a subquery is a query nested within another query. It simplifies building intricate queries to retrieve data that meets specific conditions from various tables. In this article, we present various ways of employing subqueries to create complex queries. We start by introducing SQL subqueries along with common use cases.
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7 Dec 2023
Jakub Romanowski

Free SQL Courses to Elevate Your Skills

In this article, I'll explain why LearnSQL.com offers free SQL courses. I’ll also introduce you to some of the courses we’ve offered for free over the years. If you're eager to enhance your SQL skills without breaking the bank, you've come to the right place. You're here because you understand the significance of learning SQL. But are you tired of those lengthy YouTube tutorials? How about diving into an online SQL course?
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30 Nov 2023
Maria Durkin

SQL for Data Analysis: 15 Practical Exercises with Solutions

Are you new to the world of SQL and eager to unlock the power of data analysis?. In this article, we'll improve our SQL skills through 15 practical, hands-on exercises designed specifically for beginners. Because when it comes to SQL, practice truly makes perfect! We’re going to shine a spotlight on the critical domain of data analysis, where SQL takes center stage. SQL, or Structured Query Language, plays a pivotal role in data analysis.
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28 Nov 2023
Tihomir Babic

What Are SQL Window Functions?

Need to up your data analysis game? Learn these SQL window functions here and you’ll take your analysis skills to the next level. Practice exercises and detailed explanations included! When I first heard about SQL window functions, I thought it was some strange marriage between SQL and Windows. I was wrong. The SQL window functions have nothing to do with that famous operating system. They are SQL functions that do computations on the set of rows related to the current row.
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23 Nov 2023
Alexandre Bruffa

The Best SQL Practice Challenges for Beginners

Want to get better at SQL? Dive into SQL practice challenges! They're a great way to learn and improve. In this article, we'll explore why these challenges are important and where you can find the best ones. Are you a student, a business owner, or an employee? If data is part of your work and you want to learn SQL to manage it, you’ll need to practice. And interactive SQL challenges are ideal for beginners to get comfortable with the language.
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21 Nov 2023
Maria Durkin

SQL Aggregate Functions: A Comprehensive Guide for Beginners

Are you curious about SQL aggregate functions and how they apply to real-world scenarios? In this article, we'll explore SQL aggregate functions, showcase real-world examples, and offer valuable insights on how to master them. Data aggregation is the process of taking several rows of data and condensing them into a single result or summary. When dealing with large datasets, this is invaluable because it allows you to extract relevant insights without having to scrutinize each individual data point.
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16 Nov 2023
Ignacio L. Bisso

10 GROUP BY SQL Practice Exercises with Solutions

Need to practice your SQL skills? These 10 GROUP BY practice exercises – with explanations and solutions – are a great start! GROUP BY is a powerful SQL clause that allows you to create groups of records and then calculate summary metrics (such as averages) for those groups. However, GROUP BY is often challenging for SQL learners to master. Yet, practicing GROUP BY is very important if you’re planning on using SQL.
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14 Nov 2023
Jakub Romanowski

SQL for Human Resources

Data is just as important in Human Resources as it is in other business areas. That makes SQL for HR more than just a tool; it's a game-changer. Let's dive into this transformative journey together. In the modern business world, data has become a cornerstone. It drives decisions, shapes strategies, and offers insights that were previously out of reach. Every corner of an organization, every department, is tapping into the potential of data to enhance its operations.
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9 Nov 2023
Alexandre Bruffa

SQL Practice for Students: 11 Exercises with Solutions

Calling all students! Are you SQL-curious? Want to learn or improve your SQL skills? This article has 11 SQL practice exercises with detailed solutions. Have you ever heard that “Practice makes perfect”? You probably have – that’s why you’re looking for SQL practice resources. If you want to develop strong skills or become an expert in a certain domain, you have to practice. As Rebecca McKeown wrote in her outstanding article Learning SQL?
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