NO.1 Which two are benefits of In-Memory Parallel Execution?
A. Reduction in the duplication of block images across multiple buffer caches
B. Reduction in CPU utilization
C. Reduction in the number of blocks accessed
D. Reduction in physical I/O for parallel queries
E. Ability to exploit parallel execution servers on remote instance
Answer: A,C
NO.2 Which three statements are true about histograms?
A. They capture the distribution of different values in an index for better selectivity estimates.
B. They can be used only with indexed columns.
C. They provide metadata about distribution of and occurrences of values in a table column.
D. They provide improved selectivity estimates in the presence of data skew, resulting in execution
plans with uniform distribution.
E. They help the optimizer in deciding whether to use an index or a full table scan.
F. They help the optimizer to determine the fastest table join order.
Answer: C,E,F
NO.3 You have enabled DML by issuing: ALTER session ENABLE PARALLEL DML;
The PARELLEL_DEGREE_POLICY initialization parameter is set to AUTO.
Which two options true about DML statements for which parallel execution is requested?
A. Statements for which PDML is requested will execute serially estimated time is less than the
time specified by the PARALLEL_MIN_THRESHOLD parameter.
B. Statements for which PDML is requested will be queued if the number of busy parallel
execution servers greater than PARALLEL_MIN_SERVERS parameter.
C. Statements for which PDML is requested will always execute in parallel if estimated execution
in parallel if estimated execution time is greater than the time specified bythe
PARELLEL_MIN_TIME_THRESHOLD parameter.
D. Statements for which PDML is requested will be queued if the number of busy parallel
execution servers is greater than PARELLEL_SERVERS_TARGET parameter.
E. Statement for which PDML is requested will be queued if the number of busy parallel execution
servers is greater than PARELLEL_DEGREE_LIMIT parameter.
Answer: C,D
NO.4 Which two types of column filtering may benefit from partition pruning?
A. Equally operates on range-partitioned tables.
B. In-list operators on system-partitioned tables
C. Equality operators on system-partitioned tables
D. Operators on range-partitioned tables
E. Greater than operators on hash-partitioned tables
Answer: A,D
NO.5 Which four statements are correct about communication between parallel execution process?
A. The number of logical pathways between parallel execution producers and consumers depends
on the degree parallelism.
B. The shared pool can be used for parallel execution messages buffers.
C. The large pool can be used for parallel execution messages buffers.
D. The buffer cache can be used for parallel execution message buffers.
E. Communication between parallel execution processes is never required if a query uses full
partition-wise joins.
F. Each parallel execution process has an additional connection to the parallel execution
coordinator.
Answer: A,B,E,F