The Illustrated Elephant

Users of proprietary database management systems are usually bound to use graphical modeling tools with an emphasis on drawing diagrams and generating SQL DDL code from them. The process is generally error-prone and cumbersome, being based on mediochre user interfaces and generating bad SQL representing poor data models, as diagrams can hardly represent the full richness of SQL data models — specially in an SQL flavor like PostgreSQL’s. Many databases are reverse-engineered into entity-relationship diagrams, loosing much information coded into SQL features not directly supported by the diagramming tools, or in the SQL DDL source code which originally created the reverse-engineered database.

A well-kept but open secret of many database administrators is reliance on source code and automatic diagramming tools. Breaking free from the misconception that all information should be graphically represented, or even that it should be graphically created, and from the mistaken identification of modeling and drawing, such data modelers are free to use the full power of both SQL and their well-proven, flexible source code tools, all the while generating all the graphics and web pages they could possibly want automatically, using simple, fast programs which can lay out diagrams much better than most drafters.

SQL DDL coding can also be nicely combined to literary programming tools, in what we call ‘literary modeling’: interspersing SQL DDL statements in a full text explanation of the model and the reasoning behind it, we can generate both text files for database schema creation, and nicely formatted documents for reading, browsing and reference, both printed and online. These documents can, and typically will, include graphics generated automatically from either the SQL DDL or the database schema itself.

It is our tested conviction that this process is much more pleasurable and efficient than the tradicional diagram-based one.