Which three statements are true about Automatic Degree of Parallelism (Auto DOP) on Exadata?

Which three statements are true about Automatic Degree of Parallelism (Auto DOP) on Exadata?

A.
Auto DOP is an exclusive feature in Exadata, which allows the database optimizer to evaluate
each statement and run it in parallel without special hints.

B.
Auto DOP is disabled by default and must be enabled before SQL statements can take
advantage of its features.

C.
Auto DOP is enabled by default on Oracle 11gR2, allowing full use of its features.

D.
Oracle’s Auto DOP algorithms calculate the Degree ofParallelism based on the table’s block
counts.

E.
SQL statements that take advantage of Auto DOP am be identified by using data from Oracle
Automatic Workload Repository (AWR) or Enterprise Manager’s Monitored SQL Executions page.

Explanation:
B (not c): To enable the features in 11g Release 2, use the parallel_degree_policy
parameter (by default this stuff is off – parameter is set to manual). For Auto DOP, setting this to
limited is sufficient. If you want more functionality (in-memory parallel processing and parallel
statement queuing parallel_degree_policy should be set to auto).
Incorrect:
Not A:
* What if you don’t have Exadata? Chances are that if your system is large enough to warrant Auto
DOP, it is similar enough to Exadata to behave nicely with this number.
*Auto DOP is only useful in systems with enough CPUs and disks to make concurrent parallel

processing feasible. It was designed mostly for Exadata, orfor systems of similar size. 48 CPUs
and 84 disks sound like a nice start