Summary  551

Resource Manager Statistics in AWR

The Automatic Workload Repository (AWR) introduces new views for DRM statistics. The

DBA_HIST_RSRC_PLAN and DBA_HIST_RSRC_CONSUMER_GROUP views retain historical versions of the statistics in V$RESOURCE_PLAN and V$RESOURCE_CONSUMER_GROUP. The view

V$RSRCMGRMETRIC shows resource utilization and waits due to DRM.

DBRM is the background process for the Database Resource Manager.

Summary

In this chapter, you learned about Automatic Memory Management, Automatic Shared Memory Management, manually configuring SGA parameters, Automatic PGA Memory Management, resumable space operations, transportable tablespaces, transportable databases, Segment Shrink operations, and the Database Resource Manager.

With memory management, you learned that Oracle highly recommends that you configure Automatic Memory Management and leave memory tuning and management to the Oracle instance. If you as the DBA for a database understand the application and know how to tune the SGA and PGA to achieve better results, then choose Automatic Shared Memory Management and Automatic PGA Memory Management. If you need more granular control, then manually configure your SGA and/or PGA.

You learned about resumable space allocations and how to configure, detect, and remedy suspended transactions.

You learned about transportable tablespaces and transportable databases. With transportable tablespaces, you can convert a tablespace set to run on a different platform with a different endianness using the RMAN convert clause. You cannot transport an entire database to a different endian format, but you can convert it to run on a different platform with the same endianness.

The Segment Shrink feature can be used to reclaim space both above and below the high-water mark while a segment remains online and in use.

You learned about the Oracle Database Resource Manager (DRM) and how to configure it to manage resources on your Oracle database. You can set up a pending area to hold all of the DRM objects as they are created or modified. Objects in the pending area need to be validated before moving them into the data dictionary. We discussed the requirements that each object must pass before being declared valid by the DRM. You learned that submitting the pending area activates all the objects therein and moves them into the data dictionary. To

put all of the elements together, you can build a complex resource-plan schema using PL/SQL packages and then enable the plan on the database.

552  Chapter 11  n  Managing Database Resources

Exam Essentials

Know the difference between Automatic Memory Management and Automatic Shared Memory Management.    Be able to distinguish the characteristics, pros, and cons of Automatic Memory Management. Understand how to configure Automatic Memory Management vs. Automatic Shared Memory Management. Understand the difference between

the MEMORY_TARGET and MAX_MEMORY_TARGET and the difference between SGA_TARGET and

SGA_MAX_SIZE. Understand how to dynamically increase or decrease the amount of memory usable by the instance.

Know how to manually configure the SGA.    Understand how to disable Automatic Memory Management and Automatic Shared Memory Management and how to manually configure the individual SGA pools. Know the names of the pools you can configure manually.

Know how to configure Automatic PGA Memory Management.    Understand how to explicitly and implicitly configure Automatic PGA Memory Management. Understand what instance PGA memory is used for. Understand the meaning of and how to configure Automatic PGA Memory using PGA_AGGREGATE_TARGET.

Know how to configure the Database Resource Manager.    Be able to create, update, and delete DRM objects. Be aware of the pending area and the need to validate and submit objects to the data dictionary to make them active. Know that submitting the pending area enforces validation, so it isn’t strictly necessary to validate as a separate step. Know the various methods of enabling DRM (through ALTER SYSTEM and through initialization parameters). Understand the various allocation methods.

Be able to assign users to Database Resource Manager groups.    Know all the methods of assigning user sessions to DRM groups. Know the names of the DBMS_RESOURCE_MANAGER procedures for assigning groups. Be aware of the switch privilege and how it is granted. Be aware of the DBMS_SESSION procedure that users can use to change their own group.

Know how to create resource plans within groups.    Understand all the steps involved in creating resource plans, both simple and complex. Know the difference between singleand multilevel resource plans. Understand the allocation methods used. Know what constitutes a top-level plan and a subplan.

Be able to specify directives for allocating resources to consumer groups.    Know how to create and manage plan directives to allocate resources to consumer groups and subplans. Understand which allocation methods are available for directives to groups as opposed to directives to subplans.

Review Questions

1.Which of the following Oracle features is enabled by setting a nonzero value for the MEMORY_TARGET initialization parameter?

A.Automatic PGA Memory Management

B.Automatic SGA Memory Management

C.Automatic Shared Memory Management

D.Automatic Memory Management

E.Manual SGA Memory Management

F.None of the above

2.By setting the value of MEMORY_TARGET to zero and setting the value of SGA_TARGET to a nonzero value, you will enable which of the following memory-management options?

A.Automatic PGA Memory Management

B.Automatic SGA Memory Management

C.Automatic Shared Memory Management

D.Automatic Memory Management

E.Manual SGA Memory Management

F.None of the above

3.For Oracle 11g, Oracle strongly recommends that you configure your database to use which of the following memory-management features?

A.Automatic PGA Memory Management

B.Automatic SGA Memory Management

C.Automatic Shared Memory Management

D.Automatic Memory Management

E.Manual SGA Memory Management

F.None of the above

4.To manually configure the SGA components using Oracle Enterprise Manager Memory Advisor, you can set values for which of the following initialization parameters? (Choose all that apply.)

A.DB_CACHE_SIZE

B.SHARED_POOL_SIZE

C.LARGE_POOL_SIZE

D.JAVA_POOL_SIZE

E.SGA_MAX_SIZE

F.SORT_AREA_SIZE

554  Chapter 11  n  Managing Database Resources

5.When manually configuring the SGA, which of the following parameter changes requires an instance restart to take effect?

A.DB_CACHE_SIZE

B.SHARED_POOL_SIZE

C.LARGE_POOL_SIZE

D.JAVA_POOL_SIZE

E.SGA_MAX_SIZE

F.SORT_AREA_SIZE

6.Using Oracle Enterprise Manager to set SGA pool values manually, for which of the following pools does Oracle EM offer advice to set the value appropriately? (Choose all that apply.)

A.DB_CACHE_SIZE

B.SHARED_POOL_SIZE

C.LARGE_POOL_SIZE

D.JAVA_POOL_SIZE

E.SGA_MAX_SIZE

F.SORT_AREA_SIZE

7.In Oracle 11g, by default which one of the following conditions implicitly enables Automatic PGA Memory Management?

A.Setting a nonzero value for SGA_TARGET

B.Configuring Automatic Shared Memory Management

C.Configuring Automatic Memory Management

D.Setting a nonzero value for SGA_MAX_SIZE and PGA_AGGREGATE_TARGET

E.None of the above

8.Automatic PGA Memory Management eliminates the need to manually configure which of the following initialization parameters? (Choose all that apply.)

A.SORT_AREA_SIZE

B.HASH_AREA_SIZE

C.BITMAP_MERGE_AREA_SIZE

D.CREATE_BITMAP_AREA_SIZE

E.PGA_AGGREGATE_TARGET

9.When tuning Automatic PGA Memory Management, which of the following views will provide the information specified?

A.The V$PGA_TARGET_ADVICE view shows the predicted cache hit-ratio improvement if you increase PGA_AGGREGATE_TARGET.

B.The V$PGA_TARGET_ADVICE view shows how the V$SQL_WORKAREA histogram will change if you change the value of PGA_AGGREGATE_TARGET.

C.The V$PGA_TARGET_ADVICE_HISTOGRAM view shows how the V$SQL_WORKAREA_HISTOGRAM will change if you switch between Manual and Automatic PGA Memory Management.

D.The V$PGA_TARGET_ADVICE view shows how performance will improve for the different work areas if you switch from Manual to Automatic PGA Memory Management.

10.To enable resumable space allocation for the instance, which of the following initialization parameters should you set to a nonzero value?

A.RESUMABLE_SPACE_TIME

B.RESUMABLE_SPACE

C.RESUMABLE_TIME

D.RESUMABLE_TIMEOUT

E.TIME_RESUMABLE

11.Which of the following describes how a distributed resumable transaction behaves?

A.The resumable setting on the initiating session determines the resumable conditions for the entire distributed transaction.

B.The resumable setting for the initiating instance determines the resumable conditions for the entire distributed transaction.

C.The resumable setting on the initiating session controls only that part of the transaction that occurs within the local instance; remote resumable settings determine the behavior of the distributed parts of the transaction.

D.None of the above.

12.Which of these components correctly identify the unique value of the NAME column in the

DBA_RESUMABLE view?

A.Username, instance number, session ID

B.Instance number, username, session ID

C.Instance number, session ID, username

D.Username, session ID, instance number

E.None of the above

556  Chapter 11  n  Managing Database Resources

13.Which of the following are included in a transportable tablespace set? (Choose all that apply.)

A.The datafiles that make up a self-contained group of tablespaces required for copy

B.The system tablespace

C.An export of the tablespace metadata

D.The spfile

E.All of the above

14.The following query will provide what information about transportable tablespaces for the current database? (Choose all that apply.)

select d.platform_name “Source”, t.platform_name “Compatible Targets”, endian_format

from v$transportable_platform t, v$database d where t.endian_format = (select endian_format

from v$transportable_platform t, v$database d

where d.platform_name = t.platform_name);

A.The list of target platforms having the same endian format as the source database

B.The list of target platforms requiring endian conversion

C.The list of target platforms that will not require endian conversion

D.The list of all target platforms that can receive transportable tablespaces from the source database

E.None of the above

15.When exporting metadata for the transportable tablespaces, what is the correct next step after confirming endian format?

A.Export the tablespaces using data pump.

B.Determine if the transportable set is self-contained.

C.Convert the datafiles using RMAN.

D.Copy the datafiles from source to destination.

16.Which of the following are prerequisite steps to transport a database? (Choose all that apply.)

A.Query the V$TRANSPORTABLE_PLATFORMS view in the source database to determine if the intended destination is listed.

B.Verify that there are no restrictions or limitations that the source or destination database may encounter.

C.Verify that the source and destination have the same Oracle version, critical updates, patch-set version, and patch-set exceptions.

D.Determine if you will perform the conversion on the source or destination platform.

E.None of the above.

17.Which of the following supplied functions is used to identify external tables, directories, and BFILES?

A.DBMS_TDB.CHECK_DIRECTORIES

B.DBMS_TDB.CHECK_EXTERNAL

C.DBMS_TDB.CHECK_BFILE

D.DBMS_TDB.CHECK_EXT

18.Which of the following is a prerequisite for running DBMS_TDB.CHECK_DB to a successful completion?

A.The database must be in read-write mode.

B.The database must have no external files.

C.The database must open in read-only mode.

D.The database must be mounted but not opened.

19.Which of the following options describes Segment Shrink?

A.Reclaims space above and below the high-water mark without using additional space

B.Moves rows to a new physical location, resetting the high-water mark, but uses additional space during the operation

C.Deallocates space above the high-water mark that is currently not in use

D.None of the above

20.For which of the following can you use Segment Shrink? (Choose all that apply.)

A.Heap tables

B.Tables with function-based indexes

C.Indexes

D.Partitions and subpartitions

E.None of the above

21.When shrinking a table segment, you choose to shrink all the indexes for that table using the SHRINK SPACE command. Which clause should you use?

A.INCLUDING DEPENDENCIES

B.INCLUDING DEPENDENCIES CASCADE

C.COMPACT

D.CASCADE

E.None of the above

558  Chapter 11  n  Managing Database Resources

22.Which of these represent the main components of Database Resource Manager? (Choose all that apply.)

A.Resource consumer groups

B.Resource plans

C.Resource-plan groups

D.Resource-plan directives

E.All of the above

23.Every resource plan must contain an allocation to which consumer group?

A.LOW_GROUP

B.SYS_GROUP

C.DEFAULT_GROUP

D.BASE_GROUP

E.OTHER_GROUPS

24.Which DBMS_RESOURCE_MANAGER procedure prioritizes consumer-group mappings?

A.CREATE_MAPPING_PRIORITY

B.SET_MAPPING_PRIORITY

C.SET_MAPPING_ORDER

D.PRIORITIZE_MAPPING_ORDER

E.This functionality is not available through the DBMS_RESOURCE_MANAGER package.

25.Within a resource-plan definition, what differentiates a top-level plan from a subplan?

A.A subplan has the PLAN_SUB parameter value set to SUB.

B.A top-level plan has the GROUP_OR_PLAN parameter set to the name of the subplan in the resource-plan definition.

C.There is no difference in the resource-plan definition.

D.A subplan always has the CPU_MTH parameter value set to RATIO.

E.The string TOP_LEVEL is appended to the name of top-level resource plans.