The rules surrounding technology are constantly changing. Decisions and architectures based on current technology might easily become out of date with hardware changes. To best understand how multimedia and unstructured data fit and can adapt to the changing technology, it's important to understand how and why we arrived at our different current architectural positions. In some cases we have come full circle and reinvented concepts that were in use 20 years ago. Only by learning from the lessons of the past can we see how to move forward to deal with this complex environment.
In the past 20 years a variety of architectures have come about in an attempt to satisfy some core requirements:
Allow as many users as possible to access the system
Ensure those users had good performance for accessing the data
Enable those users to perform DML (insert/update/delete) safely and securely (safely implies ability to restore data in the event of failure)
The goal of a database management system...