Oracle 1Z0-054 問題集

質問 1：
You are working as a DBA on an online transaction processing (OLTP) system. This OLTP systems runs on a machine with a single CPU, on which applications primarily perform small random I/Os where each foreground process reads a data block into the buffer cache for updates and the changed blocks are written in batches by the DBWR process. You noticed the increase in I/O requests queued up against a disk, and an increase in the wait time in queue. What would you recommend to improve the latency of I/O requests?
A. Stripe data across multiple disks.
B. Increase the value of the DB_WRITER_PROCESSES parameter.
C. Increase the size of buffer cache.
D. Decrease the value of the DBWR_IO_SLAVES parameter.
正解：A

質問 2：
The users in your online transaction processing (OLTP) environment complain that the query response time has increased considerably. On investigation, you find that the Program Global Area (PGA) is undersized and using temporary segments for sort operations. You plan to increase the size of the PGA and there is ample amount of memory available to you. You used the PGA advisor to check the correct size for PGA. View the Exhibit and examine the content of the PGA advisor. What size of PGA would give the maximum benefit?

A. 8024 MB
B. 125 MB
C. 1003 MB
D. 1404 MB
E. 1204 MB
F. 3009 MB
正解：F

質問 3：
View the Exhibit and examine the output for the WRC command-line utility that you executed to estimate the number of replay clients.Identify three prerequisites for completing the replay. (Choose three.)

A. The replay database should be in the RESTRICTED mode.
B. The replay options for think_time_scale and connect_time_scale must be set to 100 each.
C. You need to start at least 21 replay clients on six CPUs to start the replay.
D. The user should be able to use the workload replay package and should have the DBA role.
E. The replay directory must have all the replay files that have been preprocessed.
正解：C,D,E

質問 4：
Which three statements are true about performance analysis by SQL Performance Analyzer? (Choose three.)
A. It shows only the overall impact on workload.
B. It detects changes in SQL execution plans.
C. It generates recommendations to run SQL Tuning Advisor to tune regressed SQL statements.
D. The importance of SQL statements to be analyzed is based on the size of the objects accessed.
E. It produces results that can be used to create the SQL plan baseline.
正解：B,C,E

質問 5：
You received complaints from users about slow response time in some parts of the application. On investigation, you find that this happens whenever the application runs any query against the PROD_DET table that contains detailed information about all the products. You gathered the table statistics and executed the following statements to find more information about this table: SQL> SELECT chain_cnt, 2 round(chain_cnt/num_rows*100,2) pct_chained, 3 avg_row_len, pct_free , pct_used 4 FROM user_tables 5 WHERE table_name = 'PROD_DET';CHAIN_CNT PCT_CHAINED AVG_ROW_LEN PCT_FREE PCT_USED---------- ----------- ----------- ---------- ----------4789 100 3691 10 40 Which methods can you use to improve the performance? (Choose all that apply.)
A. move the table using the ALTER TABLE command
B. decrease the PCTFREE value
C. export and import the table
D. online table redefinition
正解：A,C,D

質問 6：
View the Exhibit and examine the details of the Top 5 Timed Events from an Automatic Workload Repository (AWR) report.What can be the three possible causes for the latch-related wait events? (Choose three.)

A. A large number of data definition language (DDL) and query statements are being executed simultaneously by different sessions.
B. Cursors are not being shared.
C. Shared pool size is too small.
D. A large number of COMMITs are being performed.
E. There are frequent logons/logoffs.
正解：B,C,E

質問 7：
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 time spent in processing the input/output (I/O) request by users.
B. It is the sum of the CPU time of all nonidle sessions.
C. It is the sum of wait time and the CPU time of all nonidle sessions.
D. It is the difference between the wait time and the CPU time of all nonidle sessions.
正解：C