Take a look at
http://meta.wikimedia.org/wiki/User:RichMorin/MySQL_Tables
and let me know if this doesn't answer your questions.
-r
--
http://www.cfcl.com/rdm Rich Morin
http://www.cfcl.com/rdm/resume rdm@cfcl.com
http://www.cfcl.com/rdm/weblog +1 650-873-7841
Technical editing and writing, programming, and web development