Virginia International University
CMP556, Database Management Systems
Spring I 2015
Final Exam, Due by 9:00 PM EST on Saturday, Mar 7, 2015
Please note that you are allowed to use any source including your text book, other books or publications, and the Internet to find the correct answers to the questions in the Midterm Exam. However, direct copying and pasting your answers from any sources is not acceptable, is considered plagiarism, and is against the VIU policy. Doing so will result in a grade of zero for this assignment. You should learn the materials and then submit your answers in your own wording rather than copying and pasting from other sources.
SHORT ESSAY: Write your answers in a separate document in Word (.doc/.docx) or Rich Text Format (.rtf) and post it to the course online system by deadline.
Please note that the answer to each of these questions is hardly more than half a page. So your answers must be short and to the points. Writing too much and â€œirrelevantâ€ to the question will cost you points. Also for each question you must add the source at the end of your answer (page number from the textbook or the URL from the Web).
1. Consider a disk with the following characteristics (these are not parameters of any particular disk unit): block size B=512 bytes, interblock gap size G=128 bytes, number of blocks per track=20, number of tracks per surface=400. A disk pack consists of 15 double-sided disks.
i. What is the total capacity of a track and what is its useful capacity (excluding interblock gaps)?
ii. How many cylinders are there?
iii. What are the total capacity and the useful capacity of a cylinder?
iv. What are the total capacity and the useful capacity of a disk pack?
2. After a transaction is submitted to a DBMS for execution it may fail. There are several possible reasons for a transaction to fail in the middle of execution. What are some of more common types of failures among all possible ones? Name and briefly explain at least 3 types.
3. What are some of the issues that are addressed in the area of database security? Give one example for each issue.
4. Describe some of the advantages of distributed databases and name the additional functions that that the Distributed Database Management System software must be able to provide in order to achieve the above advantages.
5. Define data mining and describe some of its applications.