As you might know, SQL is used to communicate with databases. Before you start using SQL, you need to have access to a database system.
You can try out most of the SQL commands shown in the examples throughout the tutorials using our online SQL editor. This SQL editor utilizes Web SQL Database to store and access data on the client side. However, to run some SQL commands, you'll need a complete database management system like MySQL, SQL Server, etc.
Note: Web SQL Database lets you create SQL databases and execute SQL commands on the client side. It is built on the widely-used open-source SQLite engine. Web SQL is supported by Chrome, Opera, and Safari browsers.
A relational database is organized into logical units known as tables, which are interconnected within the database. This structure allows data to be segmented into smaller, logical units, making it easier to manage and improving performance.
In a relational database system, tables are linked by common keys or fields. This means that even if the needed data is spread across multiple tables, you can join these tables to retrieve a combined data set with a single query.
Note: SQL was established as a standard by the American National Standards Institute (ANSI) in 1986, and by the International Organization for Standardization (ISO) in 1987. However, most SQL code requires some modifications to be fully compatible across different database systems.
If you don't already have a DBMS (Database Management System) installed on your computer, you have several options. You can install a free, open-source DBMS.
MySQL is the most popular and widely supported open-source database management system. It is easy to download and use, and it is available for both Windows and Linux (or UNIX) operating systems. You can download it for free from here: https://dev.mysql.com/downloads/mysql/
You can also install SQL Server Express. This is a free version of Microsoft SQL Server, allowing up to 10GB of database storage. You can download the Express edition from here: https://www.microsoft.com/en-in/download/details.aspx?id=30438.
Alternatively, if you're looking to develop applications using PHP and MySQL, consider installing WampServer or XAMPP. WampServer is a Windows-based web development environment that supports creating web applications with Apache2, PHP, and MySQL databases. It includes PhpMyAdmin, a MySQL administrative tool for managing databases through a web browser. You can download WampServer from here: http://www.wampserver.com/en/