To be really successful at working with databases, there are many different disciplines to become proficient in - things like disaster recovery, security management, data integration, and more. But there are less than a handful of things you want to be really good at; becoming super-skilled in them will help you enormously in your database career. And believe it or not, one of these key areas is data modeling and its kissing cousin, physical database design.
That's right - in the pursuit for better overall database performance, many professionals are ignoring what is perhaps the number one contributor to excellent RDBMS speed - the physical database design. This article addresses this issue and demonstrates how database pro's need to return to their foundational practices of building the right database for the right type of job.
The article continues at http://dev.mysql.com/tech-resources/articles/why-data-modeling.html