System Catalogs

I want to try and really really understand the system catalogs as a
prelude to figuring out how to make some enhancements.

I've read everything in the doco about them (which isn't much that I can
see). Is there anything else? Does it say somewhere what all the fields
mean? I'm particularly interested in the basic catalogs - classes,
attributes, types etc.


-- 
Chris Bitmead
http://www.bigfoot.com/~chris.bitmead
mailto:chris.bitmead@bigfoot.com