The feed aggregator is a powerful feature in Drupal. Here is a UML model of how it stores its data:
As of Drupal 4.6.3 and HEAD today, aggregator.module
uses a fairly simple and optimized set of five tables. This
UML diagram shows how they are logically related together.
Tagged for drupal, UML, aggregator.
2005-11-28 - Update : this page, as well as other in the Grokking Drupal series of my blog, is now available on drupal.org. The version on drupal.org will probably be updated with time, whereas this one probably won't be.