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- Question
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.
- Correct Answer
- Be careful indexing attributes that have null values.
- 1. 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
- 2. 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
- 3. 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
- 4. 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
- 5. 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. Discuss
- 6. What is the best data type definition for Oracle when a field is alphanumeric and has a length that can vary?
Options- A. VARCHAR2
- B. CHAR
- C. LONG
- D. NUMBER Discuss
- 7. Sequential retrieval on a primary key for sequential file storage has which of the following features?
Options- A. Very fast
- B. Moderately fast
- C. Slow
- D. Impractical Discuss
- 8. A multidimensional database model is used most often in which of the following models?
Options- A. Data warehouse
- B. Relational
- C. Hierarchical
- D. Network Discuss
- 9. Which of the following is an advantage of partitioning?
Options- A. Complexity
- B. Inconsistent access speed
- C. Extra space
- D. Security Discuss
- 10. A benefit of the three-tier architecture is which of the following?
Options- A. New modules can be built to support specific business needs
- B. Performance improves for compiled SQL statements
- C. Results in a thinner client and database server
- D. All of the above. Discuss
Physical Database Design problems
Search Results
Correct Answer: RAID-0.
Correct Answer: All of the above.
Correct Answer: CHAR
Correct Answer: All fields are stored in two relations.
Correct Answer: Use compatible data types.
Correct Answer: VARCHAR2
Correct Answer: Very fast
Correct Answer: Data warehouse
Correct Answer: Security
Correct Answer: New modules can be built to support specific business needs
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