4 Apr 2024 Martyna Sławińska SQL Numeric Functions Review all the SQL numeric functions, including their definitions and examples. SQL’s numeric functions perform operations on numbers. They take one or more numbers as arguments and return a number as output. Note that numbers may be of different data types, including integers, doubles, and floats. You can learn more about numeric and decimal data types here. SQL numeric functions can be divided into scalar and aggregate functions. Scalar functions compute a result for each input row individually. Read more 5 Feb 2024 Martyna Sławińska MySQL Practice: Best Exercises for Beginners These 15 MySQL exercises are especially designed for beginners. They cover essential topics like selecting data from one table, ordering and grouping data, and joining data from multiple tables This article showcases beginner-level MySQL practice exercises, including solutions and comprehensive explanations. If you need to practice … Selecting data from one table Ordering and grouping data Joining data from multiple tables … these 15 tasks are just for you! Read more 18 Jan 2024 Martyna Sławińska 18 SQL Questions for Beginners: Theory and Practice Whether you're starting or refreshing your SQL skills, join us as we work through these 18 SQL practice questions for beginners. SQL, or Structured Query Language, is a programming language used to define, retrieve, and manipulate data in relational databases. It provides an intuitive syntax of SQL statements and keywords that create, modify, and query relational databases. This article focuses on reviewing and practicing the basics of SQL. We’ll start by reviewing the SELECT statement and its required and optional components for fetching data from a single table. Read more 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. Read more 10 Oct 2023 Martyna Sławińska 5 Easy SQL INNER JOIN Examples for Beginners Looking for a clear explanation of joins in SQL? Check out these five SQL INNER JOIN examples! In SQL, INNER JOINs can be a bit difficult for beginners to master. But once you start working with them, you’ll learn they’re very useful! Let’s discuss five examples of SQL INNER JOINs. But first, let’s do a quick review of why JOINs matter. In relational databases, data is organized and stored within tables. Read more 14 Sep 2023 Martyna Sławińska 11 SQL Window Functions Exercises with Solutions In this article, we present 11 practice exercises involving SQL window functions, along with solutions and detailed explanations. SQL window functions are a powerful feature that lets us extract meaningful insights from our data easily, yet few SQL courses offer SQL window functions exercises. This makes practicing window functions quite difficult. In this article, we’ll give you 11 practice exercises that feature window functions. All exercises shown in this article come from our interactive courses Window Functions and Window Functions Practice Set. Read more 10 Aug 2023 Martyna Sławińska Advanced SQL Practice: 10 Exercises with Solutions As SQL proficiency continues to be in high demand for data professionals and developers alike, the importance of hands-on practice cannot be emphasized enough. Read on to delve into the world of advanced SQL and engage in practical exercises to enhance your skills. This article provides you with a collection of ten challenging SQL practice exercises specifically for those seeking to enhance their advanced SQL skills. The exercises cover a selection of SQL concepts and will help you refresh your advanced SQL knowledge. Read more 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. 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. Read more 8 Dec 2022 Martyna Sławińska How to Export Data From Microsoft SQL Server to a CSV File When working with data and databases, it is common to export data for further processing or transport to another database. Follow this article to learn how to export data from Microsoft SQL Server to a CSV file. In this article, we first recall what a CSV file is and why you would want to export data in this format from an MS SQL Server database. Then, we cut to the chase and export data to a CSV file using both SQL Server Management Studio (SSMS) and SQL Command Line (SQLCMD). Read more 22 Nov 2022 Martyna Sławińska How to Export Data from MySQL into a CSV File A database is a primary platform for working with data and storing data. But often, you must take your data out of the database. Read on to find out how to export data from MySQL database into a CSV file. In this article, we’ll demonstrate how to export data into a CSV file. We’ll start by introducing what a CSV file is and why we use it. Then, we’ll export data from a MySQL database into a CSV file. Read more «« « 1 2 3 » »»