01. Identify two correct statements about the Active Session History (ASH) data.
a) A part of SGA memory is used to store ASH data as rolling buffer.
b) The ASH data can be analyzed between any two small time intervals.
c) All ASH data in memory are flushed to disk by MMON in every 3 seconds.
d) All ASH data in memory are flushed to disk by MMNL process whenever the buffer is full.
02. Which three statements are true about performance analysis by SQL Performance Analyzer?
a) It detects changes in SQL execution plans.
b) It shows only the overall impact on workload.
c) It produces results that can be used to create the SQL plan baseline.
d) It generates recommendations to run SQL Tuning Advisor to tune regressed SQL statements.
e) The importance of SQL statements to be analyzed is based on the size of the objects accessed.
03. In which case is the database buffer cache NOT used?
a) when physical I/Os are performed to read from data files
b) when the database writer process writes to the SYSTEM tablespace
c) when the server process writes sort data to the temporary tablespace
d) when the database writer process writes undo data to the undo tablespace
04. What indicates that the rate of writing data blocks to the disk is very slow?
a) very high cache-hit ratio
b) increasing number of free buffer waits
c) increasing number of buffer busy waits
d) waits on latch: cache buffers chains event
05. Identify the reason why chained or migrated rows in a table cause performance degradation when you access them.
a) because the ROWID changes for these rows
b) because these rows make existing indexes invalid
c) because it is not possible to use indexes to retrieve these rows
d) because retrieving these rows requires more than one data block to be accessed
e) because the rows force queries to use temporary segments while retrieving them
06. In which two scenarios would you recommend using RAID level 5 as an option for database storage?
a) For a database with lower recovery (MTTR) overhead
b) For a database in which the applications primarily perform read operations and predominantly sequential I/O is performed
c) For a database in which performance is the primary goal of the database because applications are demanding in terms of I/O operations
d) For a database in which the database size grows rapidly, the cost of storage is critical and data accessibility is more important than performance
07. while configuring the snapshot data capture for your database, you have specified the snapshot level setting as 6.Which statistics would be captured by the Statspack report?
(Choose all that apply.)
a) resource limit
b) memory statistics
c) parent and child latches
d) segment-level statistics
e) optimizer execution plans
08. During a proactive database performance monitoring routine, on examining the AWR report you find that log file sync appears among the top 5 wait events.What does this event indicate?
a) Frequent logfile switches are occurring.
b) Redo is generated faster than LGWR can write it out.
c) Frequent commits or rollbacks are taking place in the application.
d) Frequent incremental checkpoints are taking place in the database.
09. You analyze an Automatic Database Diagnostic Monitor (ADDM) report to identify the component that contributes most to the database time. Which is the correct description of database time?
a) It is the sum of the CPU time of all nonidle sessions.
b) It is the sum of wait time and the CPU time of all nonidle sessions.
c) It is the time spent in processing the input/output (I/O) request by users.
d) It is the difference between the wait time and the CPU time of all nonidle sessions.
10. You enabled tracing for a session by executing the following command:
SQL>SET AUTOTRACE TRACEONLY;
You issued a SQL query in the same session. Which two statements are true?
a) It generates only a report on the execution path used by the SQL optimizer.
b) Trace for the statement would be created without displaying the query output.
c) It generates only the statement execution statistics without executing the query.
d) It generates a report on the execution path used by the SQL optimizer and the statement execution statistics.