You notice a performance change in your production Oracle database and you want to know which change has made this performance difference. You generate the Compare Period Automatic Database Diagnostic Monitor (ADDM) report to further investigation. Which three findings would you get from the report? (Choose three.)
Correct Answer: A,B,D
Explanation/Reference: Explanation: Keyword: shows the difference. * Full ADDM analysis across two AWR snapshot periods Detects causes, measure effects, then correlates them Causes: workload changes, configuration changes Effects: regressed SQL, reach resource limits (CPU, I/O, memory, interconnect) Makes actionable recommendations along with quantified impact * Identify what changed /Configuration changes, workload changes * Performance degradation of the database occurs when your database was performing optimally in the past, such as 6 months ago, but has gradually degraded to a point where it becomes noticeable to the users. The Automatic Workload Repository (AWR) Compare Periods report enables you to compare database performance between two periods of time. While an AWR report shows AWR data between two snapshots (or two points in time), the AWR Compare Periods report shows the difference (ABE) between two periods (or two AWR reports with a total of four snapshots). Using the AWR Compare Periods report helps you to identify detailed performance attributes and configuration settings that differ between two time periods. References:
Question 47
Which statement is true about Enterprise Manager (EM) express in Oracle Database 12c?
Examine the following parameters for a database instance: MEMORY_MAX_TARGET=0 MEMORY_TARGET=0 SGA_TARGET=0 PGA_AGGREGATE_TARGET=500m Which three initialization parameters are not controlled by Automatic Shared Memory Management (ASMM)? (Choose three.)
Correct Answer: A,E,F
Explanation/Reference: Explanation: Manually Sized SGA Components that Use SGA_TARGET Space SGA Component, Initialization Parameter /The log buffer LOG_BUFFER /The keep and recycle buffer caches DB_KEEP_CACHE_SIZE DB_RECYCLE_CACHE_SIZE /Nonstandard block size buffer caches DB_nK_CACHE_SIZE Note: * In addition to setting SGA_TARGET to a nonzero value, you must set to zero all initialization parameters listed in the table below to enable full automatic tuning of the automatically sized SGA components. * Table, Automatically Sized SGA Components and Corresponding Parameters
Question 49
You support Oracle Database 12c Oracle Database 11g, and Oracle Database log on the same server. All databases of all versions use Automatic Storage Management (ASM). Which three statements are true about the ASM disk group compatibility attributes that are set for a disk group? (Choose three.)
Correct Answer: A,B,D
Explanation Explanation: AD: The value for the disk group COMPATIBLE.ASM attribute determines the minimum software version for an Oracle ASM instance that can use the disk group. This setting also affects the format of the data structures for the Oracle ASM metadata on the disk. B: The value for the disk group COMPATIBLE.RDBMS attribute determines the minimum COMPATIBLE database initialization parameter setting for any database instance that is allowed to use the disk group. Before advancing the COMPATIBLE.RDBMS attribute, ensure that the values for the COMPATIBLE initialization parameter for all of the databases that access the disk group are set to at least the value of the new setting for COMPATIBLE.RDBMS. For example, if the COMPATIBLE initialization parameters of the databases are set to either 11.1 or 11.2, then COMPATIBLE.RDBMS can be set to any value between 10.1 and 11.1 inclusively. Not E: /The value for the disk group COMPATIBLE.ADVM attribute determines whether the disk group can contain Oracle ASM volumes. The value must be set to 11.2 or higher. Before setting this attribute, the COMPATIBLE.ASM value must be 11.2 or higher. Also, the Oracle ADVM volume drivers must be loaded in the supported environment. / You can create an Oracle ASM Dynamic Volume Manager (Oracle ADVM) volume in a disk group. The volume device associated with the dynamic volume can then be used to host an Oracle ACFS file system. The compatibility parameters COMPATIBLE.ASM and COMPATIBLE.ADVM must be set to 11.2 or higher for the disk group. Note: * The disk group attributes that determine compatibility are COMPATIBLE.ASM, COMPATIBLE.RDBMS. and COMPATIBLE.ADVM. The COMPATIBLE.ASM and COMPATIBLE.RDBMS attribute settings determine the minimum Oracle Database software version numbers that a system can use for Oracle ASM and the database instance types respectively. For example, if the Oracle ASM compatibility setting is 11.2, and RDBMS compatibility is set to 11.1, then the Oracle ASM software version must be at least 11.2, and the Oracle Database client software version must be at least 11.1. The COMPATIBLE.ADVM attribute determines whether the Oracle ASM Dynamic Volume Manager feature can create a volume in a disk group.
Question 50
You determine that database performance is sub-optimal due to hard parsing statements. Automatic Shared Memory Management (ASMM) is disabled for your database instance. Which tool would you use to get advice on how to improve performance?
