Articles Cookbook
19 Mar 2024
Jill Thornhill

SQL Aggregate Functions Cheat Sheet

A quick reference guide to using SQL aggregate functions. This SQL Aggregate Functions Cheat Sheet is designed to be your companion whenever you’re using SQL for data analysis. Aggregating data is essential for any meaningful data analysis. SQL provides a set of functions that allow you to include totals, averages, and counts in your reports and to extract the minimum and maximum value of any column of data.
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14 Mar 2024
Kamila Ostrowska

How to Install MySQL on Ubuntu

Looking to install MySQL on Ubuntu? Delve into the world of efficient data management with this comprehensive guide. From updating your package list to securing your installation and ensuring smooth configurations, these step-by-step instructions will help you seamlessly set up MySQL on your Ubuntu system. If you’re reading this article, you’re seriously interested in working with data. What you need is a suitable tool to make it happen. If you’re considering installing MySQL on an Ubuntu Linux system, you may wonder if this combination is a good choice.
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12 Mar 2024
Jeffrey Edison

Data Analyst's Guide to SQL Indexing: Fix Slow Queries

Does your SQL query response time leave something to be desired? Or maybe you don't know if your queries could be faster. In this article, we’ll explain how SQL indexing can help. Diving into SQL is like unlocking a superpower. It's all about mastering the art of querying your database effectively so you can retrieve the information you need quickly and easily. But what happens when you ask a question that's complex enough to slow response time from seconds to minutes – or even longer?
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7 Mar 2024
Nicole Darnley

Efficient Data Analysis: Leveraging SQL with R

This article delves into the nuances of using SQL with R in data analysis. It offers insights and practical examples that demonstrate the effectiveness of this combination. By integrating SQL with R, analysts can leverage the strengths of both languages. This helps them perform comprehensive data analyses, going from initial data retrieval to complex statistical modeling and visualization. To kickstart our exploration of the dynamic duo of SQL and R in data analysis, it's essential to grasp how these two powerful tools can revolutionize the way we handle, manipulate, and interpret vast datasets.
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5 Mar 2024
Maria Durkin

What Is CROSS JOIN in SQL?

What is a CROSS JOIN in SQL, and when should you use it? We answer those questions – and give you some examples of CROSS JOIN you can practice for yourself – in this article. CROSS JOINs, a type of SQL JOIN, create all possible row combinations from two tables. If you're new to JOINs and want to learn more, check out our comprehensive SQL JOINs course, which includes over 90 hands-on exercises on various JOIN types.
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1 Mar 2024
Jakub Romanowski

Course of the Month: Window Functions in PostgreSQL

Are you looking for the best way to master SQL window functions? Throughout March 2024, you can access the interactive course Window Functions in PostgreSQL for free. Boost your skills at no cost. 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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29 Feb 2024
Alexandre Bruffa

20 SQL Practice Problems for Beginner and Intermediate Users

Want to become an SQL expert? Try solving those 20 SQL practice problems! Whether you're just starting your SQL journey or preparing for exams, you need to sharpen your SQL skills if you want to become an expert. And you know what people say: practice makes perfect! Like most skills, SQL is best learned through experience; practicing SQL allows you to apply your knowledge to real-world scenarios. Through repeated practice, you'll gain the confidence to dive into complex SQL tasks and excel in both academic and professional fields.
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27 Feb 2024
LearnSQL.com Team

New Monthly SQL Practice for March 2024!

Ready for our new SQL challenge? This time, we have prepared slightly more difficult SQL tasks. Here’s the March SQL Practice course! This time, you will help Lilia who runs a genetic testing clinic. She needs insight into the performance of her clinic for February 2024 and has hired you as an SQL specialist to help her out. Can you identify the most popular tests? Can you create a report on patient preferences by age?
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27 Feb 2024
Ignacio L. Bisso

6 Examples of NTILE() Function in SQL

The SQL NTILE() function can greatly simplify your data analysis and reporting. Follow these six examples to learn what it is and when to use it. Window functions are very useful, providing great expressive power to SQL. In this article, we discuss the NTILE() function, which allows us to divide a set of records into subsets of approximately equal size. This function is widely used in financial or economic calculations.
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22 Feb 2024
Radu Gheorghiu

RIGHT JOIN in SQL: A Beginner's Tutorial

Learn RIGHT JOIN, a crucial command for any SQL specialist. Our article breaks down this essential technique, helping beginners effortlessly navigate and apply RIGHT JOIN in their database queries. In SQL, RIGHT JOIN (also known as RIGHT OUTER JOIN) is crucial for handling data effectively. This article is a beginner-friendly guide to the SQL RIGHT JOIN, an essential technique for merging different data tables. We'll walk you through the specifics of RIGHT JOIN, explaining how it stands apart from other join types in managing data.
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