Articles Cookbook
29 Jun 2023
Radu Gheorghiu

How to Use COUNT() with GROUP BY: 5 Practical Examples

Using the COUNT() function with GROUP BY is one of the most common SQL constructs in aggregate queries. Read this article to find out how to use COUNT() with GROUP BY correctly using 5 examples. In this article, we will explain the importance of using COUNT with GROUP BY. We’ll talk about why it is essential in SQL and how it enables data analysis and summarization based on specific criteria.
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27 Jun 2023
Jill Thornhill

How to Learn T-SQL Querying

T-SQL is the dialect of SQL used by Microsoft SQL Server databases. Find out the best way to learn T-SQL querying with interactive online courses. In today's data-driven world, increasing your database knowledge is always a good choice. Microsoft SQL Server is one of the most popular databases nowadays. Knowing T-SQL – the query language of SQL Server databases –is often recommended as a worthwhile skill for careers in IT, business, or research fields.
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22 Jun 2023
Maria Durkin

7 Reasons Why AI Won't Replace SQL Developers

So you've heard all about AI and the famous ChatGPT. And you're wondering if these tools would be beneficial or detrimental to your profession. In this article, we will put your fears to rest and explain how SQL and AI can work together and make developers’ jobs easier. Let's start with an explanation of what Artificial Intelligence (AI) is. AI is an area of computer science concerned with creating machines capable of performing activities that would normally need human intelligence.
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20 Jun 2023
Tihomir Babic

What Is a LEFT OUTER JOIN in SQL? 4 Practical Examples

Today’s article will discuss the LEFT OUTER JOIN in SQL. We’ll go through several examples of typical LEFT OUTER JOIN usage and compare it with INNER JOIN. A JOIN is an SQL feature that allows you to combine data from two or more tables. The nature of relational databases makes JOIN one of the most commonly used features in SQL. There are many different types of JOINs. We’ll focus on LEFT OUTER JOIN here.
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15 Jun 2023
Dominika Florczykowska

An Overview of MySQL Window Functions

MySQL window functions are very helpful when you want to create meaningful reports with SQL. In this article, we’ll demonstrate the most common window functions in MySQL and explain how to use them. MySQL 8.0 introduced a new feature: window functions. These functions are very useful to data analysts and anyone who creates reports using MySQL. Using them, you can easily compute moving averages, cumulative sums, and other calculations over specified subsets of your data.
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13 Jun 2023
Maria Durkin

Who Is a Data Manager?

Who are data managers? What are their responsibilities, and how do I become one? We’ll answer these questions and get you on your way to becoming a data manager! Simply put, data managers oversee the management of information or data within an organization. They manage data organization, storage, security, and accessibility, and they collaborate with other team members to guarantee data accuracy and usefulness in supporting decision-making. To ensure that data is effectively managed and used appropriately, they may also develop and implement policies and procedures pertaining to data management.
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8 Jun 2023
Alexandre Bruffa

Boost Data Potential with SQL and Python

In this article, we will explain why using SQL with Python is an awesome combination for unleashing the full potential of your data! Read on to find out how learning and starting to use the most popular programming language can have a positive impact on your work. You may be wondering why we write about Python on the LearnSQL.com blog? Well ... They are just a very good couple. Both languages are basic tools in such fields as data science and data visualization.
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6 Jun 2023
Martyna Sławińska

How to Use SUM() with OVER(PARTITION BY) in SQL

Discover real-world use cases of the SUM() function with OVER(PARTITION BY) clause. Learn the syntax and check out 5 different examples. We use SQL window functions to perform operations on groups of data. These operations include the mathematical functions SUM(), COUNT(), AVG(), and more. Typically, you use SUM() function with GROUP BY. In this article, we will explain what SUM() with OVER(PARTITION BY) does in SQL. We’ll show you the most common use cases in real-world applications to determine the ratio of the individual row value to the total value, calculate running totals, and find a custom order total that includes discounts for certain products.
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5 Jun 2023
LearnSQL.com Team

MySQL Cheat Sheet

Welcome to the MySQL cheat sheet! Whether you're just starting out with MySQL or you're a seasoned professional looking for a quick reference, this guide is tailor-made for you. This MySQL Cheat Sheet provides a concise and handy reference to the most commonly used MySQL commands and functionalities. It spans a range of topics, from connecting to a MySQL server and managing database contents, to the basic syntax for table creation and modification.
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1 Jun 2023
Jakub Romanowski

Course of the Month: INSERT, UPDATE, DELETE in Postgres

Do you want to be a data engineer or data analyst? Do you work with databases daily and need to expand your skills with the basics of data manipulation? You've come to the right place. For June 2023, our SQL course of the month is PostgreSQL INSERT, UPDATE, and DELETE Commands! Learn SQL for FREE! How do you get this free PostgreSQL course in June? Create a free LearnSQL.
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