The Drupal Database Design is a Comedy of Errors
http://www.hiveminds.co.uk/node/904

Hiveminds
2005

Abstract:

Drupal's database design is stupid! it sucks! it is crap! To things clearer I am talking about design errors. Yes, they do exist. Some say that design errors are the basic cause of bugs in a system. They are right. Rather than go through a bunch of queries or rather hundreds of queries, I will just say that the database design has no relational qualities that would optimize and speed up the system what so ever. This a glaring whole in the knowledge of the Development team so if you are a joiner and want to contribute to the project then think about helping them out with the database design first.