MySQL

MySQL is an open-source relational database management system that uses Structured Query Language (SQL) to manage data. It organizes data into tables with rows and columns, supports relationships between tables through foreign keys, and is known for its reliability, performance, and ease of use. MySQL is a core component of the popular LAMP and LEMP stacks.

An e-commerce site might have a MySQL database with tables for users, products, orders, and order_items. To find all orders for a specific customer with product details, you write a JOIN query: SELECT orders.id, products.name, order_items.quantity FROM orders JOIN order_items ON orders.id = order_items.order_id JOIN products ON order_items.product_id = products.id WHERE orders.user_id = 123.