Articles Cookbook
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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1 Jun 2023
Nicole Darnley

Why Do You Need SQL to Work With Google BigQuery?

Data is just as important to your business as investing or accounting; that’s why many people use Google’s BigQuery data warehouse. In this article, we'll discuss why you should learn SQL if you want to start using BigQuery. Unleash the power of your data! In the ever-growing landscape of data-driven decisions, organizations are continuously on the lookout for tools that can help them handle and analyze their data efficiently. Enter Google BigQuery: a powerful, Cloud-based data warehouse designed to store and analyze massive datasets in record time.
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30 May 2023
Gustavo du Mortier

How to Use SUM() with GROUP BY: A Guide with 8 Examples

Explore some real-world examples of using SUM() and GROUP BY in SQL, from the most basic to the most sophisticated. SUM() is a SQL aggregate function that computes the sum of the given values. GROUP BY is a SQL clause that partitions rows into groups and computes a stated aggregate function for each group. Using these two functions together, you can compute total sums for a group of rows. In this article, we’ll see 8 different examples of how you can combine SUM() and GROUP BY to create many different reports.
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25 May 2023
Maria Durkin

The Best Database Books You Should Read Now

So, you're interested in databases and looking for some database book recommendations. In this article, we’ll take a look at our top database book recommendations to feed your brain. In essence, databases are like digital filing cabinets. They have the ability to organize, store, and retrieve data. Large amounts of data are stored, managed, and made easily accessible by using databases. Additionally, databases make it possible for data to be organized into tables, which makes searching and sorting easier.
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23 May 2023
Nicole Darnley

How to Write a Recursive CTE in SQL Server

This guide will help you understand how to write and use recursive CTEs in SQL Server. Recursive CTEs are powerful tools for handling hierarchical data, and we'll break down their syntax and applications step by step. SQL Server offers a lot of powerful tools for working with data, including Common Table Expressions (CTEs). A CTE is a temporary named result set that you can reference within a SELECT, INSERT, UPDATE, or DELETE statement, often referred to as a CTE query.
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