The Impedance Imperative - Tuples + Objects + Infosets = Too Much Stuff!

Once upon a time it was possible for every new programmer to quickly learn how to write readable programs to Create, Read, Update and Delete business information. These so-called CRUD applications, along with reporting, were pervasive throughout business and essentially defined IT or MIS as it was called in those days. These IT design patterns are so pervasive that they were incorporated into numerous useful application program generators for COBOL, PLI and RPG (Synon for example) and dominated the RAD market for well over a decade. Fourth generation languages such as Adabas Natural, PowerHouse, and Mapper were designed for CRUD applications operating over complex file structures and databases. Using these tools it was straightforward for a businessperson with minimal training to develop useful robust applications. The plethora of proprietary languages and file structures was a major enabler for the late Ted Codd's [1] relational model. SQL promised a single uniform abstraction called a " relational table " and three simple and powerful operations for all applications: " Select, Project and Join ". The expressive power and uniformity of the relational model and SQL appeared very attractive to vendors who could then compete on engineering, rather than on the expressive power of their language and database structure. SQL is quite good for simple CRUD applications on normalized tables. Unfortunately, SQL isn't computationally complete and often needs to be embedded within another programming language in order to build a CRUD application. These