CS157b Fall 2002Practice Midterm 1

The practice midterm is below. Here are some facts about the actual midterm: (a) The midterm will be in class . (b) It is closed book, closed notes. Nothing will be permitted on your desk except your pen (pencil) and test. (c) You should bring photo ID. (d) There will be more than one version of the test. Each version will be of comparable difficulty. (e) If your cell-phone or beeper goes off you will be excused from the test at that point and graded on what you have done till your excusal. (f) One problem (less typos) on the actual test will be from the practice test.

1. Define the following terms and give an example:
   a. objects in identical states
   b. object having equal states


2. Explain the typical mechanism whereby objects are made persistent
   in OODBMS.

3. What is a BLOB? What is the advantage to using OODBMSs for storing
   BLOBs compared to RDBMSs?

4. Explain using actual graphs how version graphs work.

5. What kinds of things are stored in a data dictionary?

6. Suppose we have the following ER diagram

  BOOK----------------<STORED>-----BRANCH
[Code, Name, Author]            [ID, City, Phone]

  GUEST_LECTURE------------<BOOK>--------BRANCH
[Speaker, Date]                       [ID, Hamlet, Phone]
 
Suggest a possible view integration.

7. Explain when it might be useful to Horizontally partition a table
when tuning a DBMS. 

8. Give an example when one would use a Hash index over a B+-index.

9. Suggest a tuning of the following query:

   SELECT * FROM ACCOUNT WHERE Value < 0 OR ID = 123456;

   assuming we have an index on Value and ID.

10. What does it mean to denormalize a databases tables? When would you do
    it?