Preface

Most of the web applications that exist today work with data. From a simple guest book page on a personal website, to a large product catalog of an online retailer, to customer relationship management (CRM) and enterprise resource planning (ERP) systems—applications help people work with data. Working with data means dealing with CRUD. Every database application must allow users to Create, Read (or Retrieve), Update, and Delete records. A product catalog will not be functional unless users can add new products to the catalog, search for and retrieve existing products, update product information, and delete discontinued products from the catalog. Of course, a product catalog rarely exists by itself; it is usually a part of a larger e-commerce system, which has to support all CRUD operations not only for products, but also for customers, suppliers, shipping companies, orders, and more.