Oracle Database 11g Performance Tuning Presales
Oracle Database 11g Performance Tuning PreSales
1. What type of data would benefit from the use of a reverse index?
For index values which increment by 1. (*)
For any character-based index value.
For any index value with repeating sections.
For indexes with low cardinality.
Correct, a reverse index would work well for tables where the index values increment by 1.
2. When should you resort to using an hint in an SQL statement?
You should always use hints.
You should use a hint to force the optimizer into recognizing an newly added index.
You should use a hint once you understand exactly why the execution plan for the statement was used. (*)
You should never, ever use hints.
Correct, you should only use a hint in an SQL statement once you understand exactly why the execution plan for the statement was used.
3. How can the use of bind variables improve performance?
By improving the speed of selection.
By eliminating the need to parse the query. (*)
By reducing the memory requirements for a query.
By using data in data buffers.
Correct, bind variables can improve performance by eliminating the need to parse the query.
4. How does partitioning improve the performance of queries?
By optimizing joins
By sorting data in advance of queries
By partition pruning to eliminate I/O (*)
By using less network bandwidth
Correct, partitioning improves performance by partition pruning to eliminate I/O.
5. Which of the following performance-enhancing features of the Oracle Database require specific initialization parameter settings to gain their benefits?
(Choose all correct answers)
Bit-mapped indexes
Materialized views (*)
Parallelism (*)
Partitioning
None of these
Correct, you must have specific initialization parameter settings to take advantage of parallelism and materialized views.
6. A query run in parallel completes sooner than the same query run
1. What type of data would benefit from the use of a reverse index?
For index values which increment by 1. (*)
For any character-based index value.
For any index value with repeating sections.
For indexes with low cardinality.
Correct, a reverse index would work well for tables where the index values increment by 1.
2. When should you resort to using an hint in an SQL statement?
You should always use hints.
You should use a hint to force the optimizer into recognizing an newly added index.
You should use a hint once you understand exactly why the execution plan for the statement was used. (*)
You should never, ever use hints.
Correct, you should only use a hint in an SQL statement once you understand exactly why the execution plan for the statement was used.
3. How can the use of bind variables improve performance?
By improving the speed of selection.
By eliminating the need to parse the query. (*)
By reducing the memory requirements for a query.
By using data in data buffers.
Correct, bind variables can improve performance by eliminating the need to parse the query.
4. How does partitioning improve the performance of queries?
By optimizing joins
By sorting data in advance of queries
By partition pruning to eliminate I/O (*)
By using less network bandwidth
Correct, partitioning improves performance by partition pruning to eliminate I/O.
5. Which of the following performance-enhancing features of the Oracle Database require specific initialization parameter settings to gain their benefits?
(Choose all correct answers)
Bit-mapped indexes
Materialized views (*)
Parallelism (*)
Partitioning
None of these
Correct, you must have specific initialization parameter settings to take advantage of parallelism and materialized views.
6. A query run in parallel completes sooner than the same query run