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- Question
Which of the following improves a query's processing time?
Options- A. Write complex queries.
- B. Combine a table with itself.
- C. Query one query within another.
- D. Use compatible data types.
- Correct Answer
- Use compatible data types.
- 1. If a denormalization situation exists with a one-to-one binary relationship, which of the following is true?
Options- A. All fields are stored in one relation.
- B. All fields are stored in two relations.
- C. All fields are stored in three relations.
- D. All fields are stored in four relations. Discuss
- 2. Which of the following is not a factor to consider when switching from small to large block size?
Options- A. The length of all of the fields in a table row.
- B. The number of columns
- C. Block contention
- D. Random row access speed Discuss
- 3. The blocking factor is:
Options- A. a group of fields stored in adjacent memory.
- B. the number of physical records per page.
- C. attributes grouped together by the same primary key.
- D. attributes grouped together by the same secondary key. Discuss
- 4. Selecting a data type involves which of the following?
Options- A. Maximize storage space
- B. Represent most values
- C. Improve data integrity
- D. All of the above. Discuss
- 5. A secondary key is which of the following?
Options- A. Nonunique key
- B. Primary key
- C. Useful for denormalization decisions
- D. Determines the tablespace required Discuss
- 6. If a denormalization situation exists with a many-to-many or associative binary relationship, which of the following is true?
Options- A. All fields are stored in one relation.
- B. All fields are stored in two relations.
- C. All fields are stored in three relations.
- D. All fields are stored in four relations. Discuss
- 7. What is the best data type definition for Oracle when a field is alphanumeric and has a fixed length?
Options- A. VARCHAR2
- B. CHAR
- C. LONG
- D. NUMBER Discuss
- 8. Which of the following are integrity controls that a DBMS may support?
Options- A. Assume a default value in a field unless a user enters a value for that field.
- B. Limit the set of permissible values that a field may assume.
- C. Limit the use of null values in some fields.
- D. All of the above. Discuss
- 9. The fastest read/write time and most efficient data storage of any disk array type is:
Options- A. RAID-0.
- B. RAID-1.
- C. RAID-2.
- D. RAID-3. Discuss
- 10. A rule of thumb for choosing indexes for a relational database includes which of the following?
Options- A. Indexes are more useful on smaller tables.
- B. Indexes are more useful for columns that do not appear frequently in the WHERE clause in queries.
- C. Do not specify a unique index for the primary key of each table.
- D. Be careful indexing attributes that have null values. Discuss
Physical Database Design problems
Search Results
Correct Answer: All fields are stored in one relation.
Correct Answer: The number of columns
Correct Answer: the number of physical records per page.
Correct Answer: Improve data integrity
Correct Answer: Nonunique key
Correct Answer: All fields are stored in two relations.
Correct Answer: CHAR
Correct Answer: All of the above.
Correct Answer: RAID-0.
Correct Answer: Be careful indexing attributes that have null values.
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