Two styles of database development

This book is about how to write the best software code inside a relational database. The major goal is to reveal the opposition between two possible styles of development. The first style is specific to application developers. It is an atomic, row and procedural oriented style inspired by the structured models of programming. This is the classic style of programming. Many application developers write in the relational database exactly like in the user interface. By opposition, the other style of development is holistic, data set and SQL oriented. This is the style of a database developer. The purpose of the book is to compare the two styles and to promote the holistic style of development as the most suitable one. Secondly, the set based and holistic style of development is not promoted enough in universities and many application developers are not fully aware of it. There are many performance issues all over the world in relational databases due to the use of the atomic and inappropriate style of programming. The book addresses especially to application developers who write atomically in relational databases, but also to students in IT universities who should be aware of the two alternate styles of development. A good developer should realize the difference between the two specific styles and should be able to change something in the way of writing code when switching to a relational database. The first part of the book is conceptual. The goal is to explain, describe and compare the two styles of development. The second part is highly practical. I described a series of practices, taken from two popular systems like Oracle and SQL Server. I imagined many business scenarios, I described them and I solved them in the two opposite approaches. I showed that, in most of the cases, a holistic solution is available as an alternative to an atomic one. This is also a book about performance. For a good performance inside a relational database, the first thing that should be done is to write correctly. And writing correctly means writing differently and specific, means writing holistic and set based. The first prerequisite for a good performance is the use of most suitable style of development. The style of development is a vague concept, but a critical one. We, as programmers, should all be aware of our styles and try to be dynamic and adopt the most suitable style according to our needs.