SPECIAL IMPLEMENTATION CONSIDERATIONS - Database Design and Development: An Essential Guide for IT Professionals - page 414

6. List and explain any four data types supported by SQL.
7. What are the three primary clauses in an SQL query? Describe the function
of each clause.
8. How is data modification done in SQL? Describe with an example.
9. List the steps in query processing. Describe the tasks carried out in two of
these steps.
10. What is cost-based query optimization? How does the optimizer compute
costs?
EXERCISES
1. Match the columns:
1. query validating A. eliminate duplicates in result
2. delete row B. rule-based
3. distinct specification in SQL C. directly access database
4. QBE D. call-level interface to database
5. float E. verify relation names
6. index height F. verify query semantics
7. heuristic query optimization G. data type in SQL
8. API H. used by query optimizer
9. query parsing I. data maintenance function
10. embedded SQL J. adopts a visual approach
2. Create a relational data model for a doctor's office consisting of the follow-
ing objects: PATIENT, DOCTOR, VISIT, SERVICE, and BILLING. Using
SQL, code data definition statements to create the schema for this database.
3. Write five different SQL queries using the above DOCTOR database. Explain
the functions of the SQL statements in each of the queries.
4. Write five different SQL data control commands granting and revoking access
privileges to the above DOCTOR database. Explain the purpose of each
command.
5. You are the database administrator in a database project for an airline
company. Write a memo to your project manager describing the functions of
the query optimizer of your DBMS. Discuss the two common approaches, and
state your preference with reasons.