I think I first heard the term "Thick Database" in a presentation by Dr. Paul Dorsey at the ODTUG conference in 2007.
I prefer the slightly more hip term "Fat Database", and offer my own definition of the term:
"Building applications using the Fat Database approach means leveraging the full potential of the database engine and its features, rather than treating the database as a bit bucket. If a problem can be solved using the database, it should be solved using the database, rather than in a programming language outside the database."
In other words, the exact opposite of the current trend, which is to avoid any database feature except basic tables. The enterprise architecture astronauts would rather reinvent the wheel over and over again, using the latest silver bullet in the endless stream of "new and improved" languages and frameworks that appear (and disappear) every few years.
Benefits of the Fat Database approach include reduced cost and complexity, increased performance, and a degree of immunity against the need to constantly rewrite code in a rapidly changing technology landscape.
Here is a collection of links to presentations and papers related to the Fat Database approach:
Dr. Paul Dorsey, co-author of seven Oracle Press books on Designer, Database Design, Developer, and JDeveloper
- Thick Database Techniques for Fusion (and other Web) Developers
- Examining the Logic behind Database Independence
- Oracle Fusion Middleware: Tales from the Trenches
- The Helsinki Declaration (blog)
- Building Robust Applications in a DB-Centric Way
- A Database Centric Approach to J2EE Application Development
- Lucas Jellema (Oracle ACE): Optimal Use of Oracle Database 10g and Oracle Database 11g for Modern Application Development
- Mike Ault: The Myth of Database Independence
- Tom Kyte (AskTom): "Why [do we need an] application server?"