>Hello, Vista. I know your area very well.
Hello Palo Alto. (ahem! in my best W.C. Fields imitation) ...All things considered...I'd rather be in Palo Alto!
Look into
Codd's relational model. First order, second order, etc.
I'll try to surf this out on my own, but a more specific reference would help.
"The Iron Fish: The water is cold...but the fish don't mind"
...Jay Jenks, boyhood chum