ICS 132: Homework #2

Distributed: Wendesday Jan 24
Due: 11am, Wednesday Jan 31

1.

Take the database below, which describes papers that have been submitted to a conference, with details of their authors, the authors' institutions, and the URL where the papers are stored. Successively transform this database into (a) first normal form, (b) second normal form, and then (c) third normal form. Assume titles are unique.

Title	Author 1	Institution 1	Author 2	Institution 2	Author 3	Institution 3	URL
Database Technology in Organizations	Joe Blow	UCLA					http://www.ucla.edu/~blow/paper.pdf
An Analysis of Flaming	Sara Dull	CMU	Robert Wrong	CMU			http://www.dull.org/email.pdf
Gizmatron Design	Paul Gizmo	Gizmatronics					http://www.gizmo.com/design.html
Information and Context	Helen Troy	MIT	Joan Arc	MIT	Anne Cleeves	MIT	http://www.mit.edu/~ht/info.html
Breaking Database Security	T. Secret	NSA	A. Spy	CIA			http://www.nsa.gov/secure.ps

 

2

The Internet Domain Name Service (DNS) maps domain names such as www.ics.uci.edu to IP addresses such as 128.195.1.73. It is a radically distributed database, incorporating servers all over the net.

Give one technical reason and one organizational reason why a distributed design is better than a centralized one. What are the dangers of decentralization in this case?

How does the DNS manage consistency? (Hints: What sorts of inconsistency could arise? Why don't they arise all the time? What mechanisms does DNS use to limit the problems?)