Computer Science 455

Exam #3 review

Disclaimer: I have attempted to be comprehensive in the following, but important items may have been omitted by mistake. If you see such an omission, please let me know, but you are responsible for all of the lecture material to date.

• Course notes
• Elmasri and Navethe
  • Section 6.5
  • Chapter 7
  • Sections 8.1 and 8.3
• Sunderraman, chapters 2 and 4
• Relational Algebra handout
• Lectures through Tuesday's lecture/demonstration on menus.

1. Be able to write complex queries in SQL. In particular, be able to use aggegrate functions, group by / having, subqueries, exists and not exists, and the relational algebra operators in SQL.
2. Be able to write queries in the full relational algebra (including divideby).
3. Be able to describe the differences between the relational algebra and the (tuple) relational calculus, and explain where SQL fits into this.
4. Be able to explain what a trigger is, and the role triggers play in SQL*Forms.
5. Be able to explain what the "impedance mismatch" problem is, and how PL/SQL gets around the problem (by the way - this is the same way that SQL code embedded in a procedural language solves the problem.)
6. Be able to explain informally and briefly how you would go about generating a simple report, a simple form, and a simple menu. Any questions of this sort will be very basic and will be designed (I hope) so that they can be answered if you have done this two - three times.