Put Your Business Rules In Your Database

“Maybe you know how to drive a car. Maybe you can fix the
carburetor. You probably don’t assume that you know how to design
the car. However, programmers who can write huge SQL statements and
understand the output of an EXPLAIN statement often assume that
they can design a database. Admittedly, unless we’re comparing
Oracle 9i with the 1967 Volkswagen Beetle, databases usually
aren’t more complex than cars, but a properly
designed database can be very hard to come by yet it’s the key to a
solid application.

“Recently, a friend asked for help with a programming problem
and I agreed to take a look. After hearing a bit of explanation of
the problem domain, and taking a poke and what he had, I realized
that while his code was indeed buggy, the underlying bug stemmed
from bad database design in an older version of MySQL (some version
4, but I don’t recall the exact one)…”

Complete Story