Re: 1st and 2nd NF
Date: Fri, 05 Dec 2003 11:46:32 -0800
Ryan Gaffuri wrote:
> I have a college textbook and it discuss 3-6 NF and BCNF, but totally
> skips 1NF and 2NF. can someone help me in understanding this? I dont
> need it for school, I just want to know what it is.
2NF means: 1) It is in 1NF, and 2) There are no FDs where a part of (not the entire) candidate key is the determinant. This only really matters for composite keys. IE, if (a,b) are a composite candidate key, there can be no FDs of the form a-->x or b-->x.
University of California Received on Fri Dec 05 2003 - 20:46:32 CET