>I don't remember which MVP I stole this example from (was it you, Jim?), but say you have a numeric field to store the day of the week. A Database Rule is that the values must be between 1 and 7 (or 0 and 6, depending on how you count it). A Business Rule is that you are never open on weekends. If you put that in the database, and then have a special sale on Saturday, you have no way to enter that, because the Database won't let you.

Garrett,

Exactly, although I always use the State example. A field for state abbreviation should accept all valid two letter codes even if the business only works in two of them. The limitaiton to the two is a business rule.