1z1-084試験問題でリアルに更新された問題PDF
合格させる無料保証付きクイズ2024年最新の実際に出ると確認されたOracle
Oracle 1z1-084 認定試験の出題範囲：
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Oracle 1Z0-084試験に合格することは、Oracle Database 19cのパフォーマンスを管理・最適化する能力を示すことで、どんなITプロフェッショナルにとっても大きな成果です。この領域での認定は、雇用主から高く評価され、より良い求人機会や高い給与につながる可能性があります。試験勉強には、データベースパフォーマンスチューニングの概念に関する強い理解とOracle Database 19cで幅広い実務経験が必要です。
Oracle 1Z0-084試験は、Oracle Database 19Cのパフォーマンスの調整と管理に関する専門家のスキルと知識を描写する認定です。試験に合格した立候補は、Oracleデータベースの管理と調整における習熟度を検証して、その効率とパフォーマンスを最大化します。この認定は、非常に競争の激しい雇用市場における候補者の信頼性と雇用の見通しも強化します。この認定試験は、世界中の企業におけるデータベース管理、開発、および管理の役割において、キャリアをより高いレベルの責任に進めようとする専門家に最適です。
質問 # 15
Which three types of statistics are captured by statspack with snap level 6?
- A. Parent and child latches
- B. Optimizer execution plans
- C. Plan usage data
- D. Enqueue statistics
- E. Segment-level statistics
- F. Parent and child latches
正解：D、E、F
解説：
Statspack is a performance diagnostic tool provided by Oracle prior to the introduction of the Automatic Workload Repository (AWR). At snap level 6, Statspack captures the following types of statistics:
* A (Correct):Parent and child latches are captured. Latch statistics provide information about contention for latches, which are low-level serialization mechanisms used by Oracle.
* E (Correct):Enqueue statistics, which provide information on the waits for locks that manage the concurrency between users.
* F (Correct):Segment-level statistics, which provide detailed information on database segments such as tables, indexes, etc., to identify I/O and contention issues.
* C (Incorrect):While optimizer execution plans are an essential aspect of performance tuning, detailed execution plan capture is not part of the Statspack report at level 6.
* D (Incorrect):Plan usage data refers to how frequently a plan is being used, which is more associated with AWR and not typically captured in Statspack reports.
References:
* Oracle Database Performance Tuning Guide:Using Statspack
質問 # 16
Examine this code block, which executes successfully:
DBMS_SERVER_ALERT. SET_THRESHOLD (
DBMS_SERVER_ALERT.CPU_TIME_PER_CALL, DBMS_SERVER_ALERT. OPERATOR_GE, '8000', DBMS_SERVER_ALERT.OPERATOR_GE, '10000', 1, 2, 'inst1', DBMS_SERVER_ALERT.OBJECT_TYPE_SERVICE, 'main.regress.rdbms.dev.us.example.com') ;
What will happen?
- A. A warning alert will be issued only when CPU time exceeds 10000 microseconds for each user call.
- B. A critical alert will be issued when CPU time exceeds 2 minutes for each user call.
- C. A critical alert will be issued when CPU time exceeds 10000 microseconds for each user call.
- D. A warning alert will be issued when CPU time exceeds 1 minute for each user call.
正解：C
解説：
In the provided code block, theDBMS_SERVER_ALERT.SET_THRESHOLDprocedure is used to set alert thresholds for the CPU time per call in Oracle Database. This procedure is a part of Oracle's Database Server Alert system, which monitors various metrics and generates alerts when certain thresholds are exceeded.
The parameters passed to theSET_THRESHOLDprocedure are as follows:
* The first parameterDBMS_SERVER_ALERT.CPU_TIME_PER_CALLspecifies the metric for which the threshold is being set, in this case, the CPU time consumed per database call.
* The second and third parametersDBMS_SERVER_ALERT.OPERATOR_GEand'8000'specify the warning threshold level and its value, respectively. However, these are not relevant to the answer as they are overridden by the critical threshold settings.
* The fourth and fifth parametersDBMS_SERVER_ALERT.OPERATOR_GEand'10000'set the critical threshold level and its value. This means that a critical alert will be generated when the CPU time per call exceeds 10000 microseconds.
* The remaining parameters specify the warning and critical alert intervals, the instance name, the object type, and the service name. These are not directly relevant to the behavior described in the options.
Thus, the correct answer is B, as the critical threshold for CPU time per call is set to 10000 microseconds, and the system is configured to issue a critical alert when this threshold is exceeded.
References:
* Oracle Database 19c documentation on theDBMS_SERVER_ALERT.SET_THRESHOLDprocedure, which details the parameters and usage of this procedure for setting alert thresholds within Oracle Database monitoring system.
* Oracle Database Performance Tuning Guide, which provides best practices and methodologies for monitoring and tuning Oracle Database performance, including the use of server alerts and thresholds.
質問 # 17
A database instance is suffering poor I/O performance on two frequently accessed large tables.
No Big Table caching occurs in the database.
Examine these parameter settings:
Which are two actions either one of which will allow Big Table caching to occur?
- A. Increasing DB_CACHESIZE to 1 G
- B. Increasing DB_BIG_TABLE_CACHE_PERCENT_TARGET to at least 25
- C. Setting PARALLEL_DEGREE_POLICYADAPTIVE
- D. Setting DB_KEEP_CACHE_SIZE to at least 50M
- E. Increasing DB_BIG_TABLE_CACHE_PERCENT_TARGET to at least 50
- F. Setting PARALLEL_DEGREE_POLICYAUTO
正解：A、B
解説：
Big Table caching is a feature that allows frequently accessed large tables to be cached in memory to improve I/O performance. From the parameter settings provided, Big Table caching is not occurring because DB_BIG_TABLE_CACHE_PERCENT_TARGETis set to 10, which is the minimum threshold for enabling the feature, but the size of the cache is too small for the big tables to be effectively cached.
To enable Big Table caching, one of the following actions could be taken:
* C (Correct):IncreasingDB_BIG_TABLE_CACHE_PERCENT_TARGETto at least 25. This action would allocate a larger percentage of the buffer cache for storing big tables, which could allow for caching large tables and thus improve I/O performance.
* D (Correct):IncreasingDB_CACHE_SIZEto 1G. Since the size of the buffer cache is a determining factor for how much data can be cached, increasing this parameter would provide more memory space for big tables to be cached.
Options A, B, E, and F will not enable Big Table caching because:
* A:IncreasingDB_BIG_TABLE_CACHE_PERCENT_TARGETto 50 without adjusting the overall size of the cache might still not be sufficient if theDB_CACHE_SIZEis not large enough to hold the big tables.
* B:SettingDB_KEEP_CACHE_SIZEto at least 50M only specifies a separate buffer pool for objects with the KEEP cache attribute and does not affect Big Table caching.
* E:andF:Changing thePARALLEL_DEGREE_POLICYtoADAPTIVEorAUTOinfluences the behavior of parallel execution but does not directly enable or influence Big Table caching.
References:
* Oracle Database Performance Tuning Guide:Big Table Caching
* Oracle Database Reference:DB_BIG_TABLE_CACHE_PERCENT_TARGET
* Oracle Database Reference:DB_CACHE_SIZE
質問 # 18
Which two statements are true about cursor sharing?
- A. Adaptive Cursor Sharing requires histograms on filtered columns, used in equality predicates, to allow different execution plans to be generated for statements whose bound values would normally generate different plans at hard parse time.
- B. Adaptive Cursor Sharing guarantees that a suboptimal plan will never be used on any execution of a SQL statement.
- C. Setting optimizer_capture_sql_plan_baselines to TRUE loads all adaptive plans for the same statement into the cursor cache.
- D. Setting cursor_sharing to EXACT prevents Adaptive Cursor Sharing from being used.
- E. Setting Cursor_sharing to FORCE can result in a plan that is suboptimal for the majority of values bound to a bind variable when executing a cursor with one or more bind variables.
正解：D、E
解説：
A: WhenCursor_sharingis set toFORCE, Oracle tries to avoid hard parses by replacing literals in SQL statements with bind variables, even if the original statement didn't include bind variables. This can lead to the use of a single execution plan for multiple executions of a statement with different literal values, which might not be optimal for all executions.
D: Settingcursor_sharingtoEXACTensures that SQL statements must match exactly for them to share a cursor. This setting prevents the use of Adaptive Cursor Sharing (ACS) since ACS relies on the ability to share cursors among similar statements that differ only in their literal values. WithEXACT, there's no cursor sharing for statements with different literals, hence no opportunity for ACS to operate.
References:
* Oracle Database SQL Tuning Guide, 19c
* Oracle Database Reference, 19c
質問 # 19
Buffer cache access is too frequent when querying the SALES table. Examine this command which executes successfully:
ALTER TABLE SALES SHRINK SPACE;
For which access method does query performance on sales improve?
- A. db file scattered read
- B. index range scan
- C. index full scan
- D. db file sequential read
正解：D
解説：
The SHRINK SPACE operation compacts the table, which can reduce fragmentation and thus improve performance for sequential reads of the table. This operation could improve full table scans, which are typically associated with db file sequential read wait events.
References:
* Oracle Database Administrator's Guide, 19c
質問 # 20
Database performance has degraded recently.
index range scan operations on index ix_sales_time_id are slower due to an increase in buffer gets on sales table blocks.
Examine these attributes displayed by querying DBA_TABLES:
Now, examine these attributes displayed by querying DBA_INDEXES:
Which action will reduce the excessive buffer gets?
- A. Re-create the SALES table using the columns in IX_SALES_TIME_ID as the hash partitioning key.
- B. Re-create index IX_SALES_TIME_ID using ADVANCED COMPRESSION.
- C. Partition index IX_SALES_TIME_ID using hash partitioning.
- D. Re-create the SALES table sorted in order of index IX_SALES_TIME_ID.
正解：B
解説：
Given that index range scan operations onIX_SALES_TIME_IDare slower due to an increase in buffer gets, the aim is to improve the efficiency of the index access. In this scenario:
* B (Correct):Re-creating the index usingADVANCED COMPRESSIONcan reduce the size of the index, which can lead to fewer physical reads (reduced I/O) and buffer gets when the index is accessed, as more of the index can fit into memory.
The other options would not be appropriate because:
* A (Incorrect):Re-creating theSALEStable sorted in order of the index might not address the issue of excessive buffer gets. Sorting the table would not improve the efficiency of the index itself.
* C (Incorrect):Using the columns inIX_SALES_TIME_IDas a hash partitioning key for theSALES table is more relevant to data distribution and does not necessarily improve index scan performance.
* D (Incorrect):Hash partitioning the index is generally used to improve the scan performance in a parallel query environment, but it may not reduce the number of buffer gets in a single-threaded query environment.
References:
* Oracle Database SQL Tuning Guide:Managing Indexes
* Oracle Database SQL Tuning Guide:Index Compression
質問 # 21
You execute the following:
EXECUTE DBMS_AuTO_TASK_ADMIN.DISABLE;
Which advisor remains enabled?
- A. Automatic Segment Advisor
- B. Automatic Optimizer Statistics Collection
- C. Automatic SQL Tuning
- D. Optimizer Statistics Advisor
- E. SQL Plan Management Evolve Advisor
正解：B
解説：
When you executeDBMS_AUTO_TASK_ADMIN.DISABLE, it disables all automated maintenance tasks related to the Auto Task framework. This includes tasks such as the Automatic SQL Tuning Advisor, Automatic Segment Advisor, and others. However, the Automatic Optimizer Statistics Collection (D) remains enabled as it is not part of the Auto Task framework. The gathering of optimizer statistics is controlled separately and is a critical part of the database's self-tuning mechanism to ensure the optimizer has up-to-date information about the data distribution within tables and indexes.
References
* Oracle Database 19c PL/SQL Packages and Types Reference - DBMS_AUTO_TASK_ADMIN
* Oracle Database 19c Database Administrator's Guide - Managing Optimizer Statistics
質問 # 22
Which procedure gathers statistics that are always used in the generation of any execution plan?
- A. DBMS_STATS.GATHER_SYSTEM_STATS
- B. DBMS_STATS.GATHER_DICTIONARY_STATS
- C. DBMS_STATS.GATHER_DATABASE_STATS
- D. DBMS_STATS.GATHER_FIXED_ OBJECTS_STATS
正解：C
解説：
TheDBMS_STATS.GATHER_DATABASE_STATSprocedure is used to gather statistics for all schema objects in the database that do not have up-to-date statistics. These statistics are essential for the optimizer to make informed decisions about the most efficient way to execute a query. The procedure collects statistics such as table and column statistics, index statistics, and system statistics, which are all used in the execution plan generation.
References:
* Oracle Database PL/SQL Packages and Types Reference, 19c
* Oracle Database Performance Tuning Guide, 19c
質問 # 23
Which two statements are true about space usage in temporary tablespaces?
- A. When a global temporary table instantiation is too large to fit in memory, space is allocated in a temporary tablespace.
- B. When a session consumes all temporary tablespace storage, then the session would hang until the temporary space used by that session is cleared.
- C. A sort will fail if a sort to disk requires more disk space and no additional extent can be found/allocated in/for the sort segment.
- D. Lack of temporary tablespace space for sort operations can be prevented by using temporary tablespace groups.
- E. Temporary tablespaces setting Includes quotas to limit temporary space used by a session for that Temporary tablespace.
正解：A、D
解説：
Regarding space usage in temporary tablespaces, the following statements are true:
* A (Correct):When a global temporary table or a sort operation exceeds the available memory, Oracle Database allocates space in a temporary tablespace to store the temporary data or intermediate results.
* E (Correct):Using temporary tablespace groups can prevent insufficient temporary tablespace for sort operations by providing a collective pool of space from multiple temporary tablespaces, which can be used for user sorting operations.
The other options provided have inaccuracies:
* B (Incorrect):Oracle does not provide a mechanism for setting quotas on temporary tablespaces. Quotas can be set for permanent tablespaces but not for temporary ones.
* C (Incorrect):A sort operation may fail due to insufficient space, but Oracle will attempt to allocate space in the temporary tablespace dynamically. If no space can be allocated, an error is returned rather than a sort failure.
* D (Incorrect):If a session consumes all available temporary tablespace storage, Oracle will not hang the session; it will return an error to the session indicating that it has run out of temporary space.
References:
* Oracle Database Administrator's Guide:Managing Space for Schema Objects
* Oracle Database Concepts:Temporary Tablespaces
質問 # 24
For which two actions can SQL Performance Analyzer be used to assess the impact of changes to SQL performance?
- A. storage, network, and interconnect changes
- B. changes to database initialization parameters
- C. operating system and hardware migrations
- D. operating system upgrades
- E. database consolidation for pluggable databases (PDBs)
正解：B、E
解説：
SQL Performance Analyzer (SPA) can be used to assess the impact of different types of changes on SQL performance. These changes can include database initialization parameters, which can significantly affect how SQL statements are executed and therefore their performance. SPA allows you to capture a workload before and after the change and compare the performance of each SQL statement.
Database consolidation, including moving to pluggable databases (PDBs), can also affect SQL performance.
SPA can analyze the SQL workload to see how consolidation impacts performance, by comparing metrics such as elapsed time and CPU time before and after the consolidation.
References:
* Oracle Database SQL Tuning Guide, 19c
* Oracle Database Performance Tuning Guide, 19c
質問 # 25
A Standard Edition production database has performance problems for two hours on the same day each week.
Which tool must you use to diagnose the problem?
- A. Database Replay
- B. SQL Performance Analyzer
- C. Statspack report
- D. AWR Compare Periods report
正解：C
解説：
For a Standard Edition production database, the Statspack tool is available to diagnose performance problems.
The Automatic Workload Repository (AWR) and its related tools like AWR Compare Periods report and SQL Performance Analyzer are features of the Oracle Database Enterprise Edition and are not available in Standard Edition. Database Replay is also a feature of the Enterprise Edition. Statspack is a performance diagnostic tool provided for earlier versions and Standard Editions of the Oracle Database to collect, store, and analyze performance data.
References
* Oracle Database 19c Administrator's Guide - Using Statspack to Diagnose Database Performance Issues
質問 # 26
You want to reduce the amount of db file scattered read that is generated in the database.You execute the SQL Tuning Advisor against the relevant workload. Which two can be part of the expected result?
- A. recommendations regarding the creation of additional indexes
- B. recommendations regarding the creation of SQL Patches
- C. recommendations regarding partitioning the tables
- D. recommendations regarding the creation of materialized views
- E. recommendations regarding rewriting the SQL statements
正解：A、D
解説：
The SQL Tuning Advisor provides recommendations for improving SQL query performance. This may include suggestions for creating additional indexes to speed up data retrieval and materialized views to precompute and store query results.References:
* Oracle Database SQL Tuning Guide, 19c
質問 # 27
A database supporting a mixed workload is hosted on a server with 64 CPUs.
A large number of free buffer waits and buffer busy waits occur affecting performance.
The buffer cache size was then increased but after a few hours, the same wait events occur more often than before the change.
Examine these parameter settings:
Which two actions can help reduce the number of these waits7
- A. Increasing the size of MEMORYTARGET
- B. increasing the value of DB_FILE_MULTIBLOCK_READ_COUNT to 128
- C. reducing the values of DB_FILE_MULTILOCK_READ_COUNT to 64
- D. setting dbwr_io_slaves to 64
- E. increasing the value of DBWRITERPROCESSES to 64,
正解：D、E
解説：
Given a server with 64 CPUs, if the buffer cache size increase did not alleviate free buffer waits and buffer busy waits, one can look into optimizing I/O and the efficiency of the DB writer processes.
C: Setting theDBWR_IO_SLAVESparameter to a non-zero value, such as the number of CPUs, would initiate I/O slave processes to assist the DB writer process. This can help reduce I/O contention when writing from the buffer cache to disk, particularly for systems without asynchronous I/O capabilities.
D: Increasing the value ofDBWRITERPROCESSESenables multiple DB writer processes to be active simultaneously. In a system with many CPUs, such as 64, increasing this value can improve the write throughput to disk and potentially reduce buffer busy waits.
References:
* Oracle Database Reference, 19c
* Oracle Database Performance Tuning Guide, 19c
質問 # 28
Examine this statement and output:
Which two situations can trigger this error?
- A. The capture directory is part of the root file system.
- B. The syntax is incomplete.
- C. The instance is unable to access the capture directory.
- D. The user lacks the required privileges to execute the DBMS WORKLOAD CAPTURE package or the directory.
- E. There is a file in the capture directory.
正解：C、D
解説：
The ORA-15505 error indicates that the instance encountered errors while trying to access the specified directory. This could be due to:
A: Insufficient privileges: The user attempting to start the workload capture might not have the required permissions to execute the DBMS_WORKLOAD_CAPTURE package or to read/write to the directory specified.
E: Accessibility: The database instance may not be able to access the directory due to issues such as incorrect directory path, directory does not exist, permission issues at the OS level, or the directory being on a file system that's not accessible to the database instance.
References:
* Oracle Database Error Messages, 19c
* Oracle Database Administrator's Guide, 19c
質問 # 29
You want to reduce the amount of db file scattered read that is generated in the database.You execute the SQL Tuning Advisor against the relevant workload. Which two can be part of the expected result?
- A. recommendations regarding the creation of additional indexes
- B. recommendations regarding the creation of SQL Patches
- C. recommendations regarding partitioning the tables
- D. recommendations regarding the creation of materialized views
- E. recommendations regarding rewriting the SQL statements
正解：A、D
解説：
The SQL Tuning Advisor provides recommendations for improving SQL query performance. This may include suggestions for creating additional indexes to speed up data retrieval and materialized views to precompute and store query results.References:
* Oracle Database SQL Tuning Guide, 19c
質問 # 30
Which Optimizer component helps decide whether to use a nested loop join or a hash join in an adaptive execution plan?
- A. Statistics Feedback
- B. SQL Plan Directives
- C. Statistics Collector
- D. Dynamic Statistics
- E. Automatic Reoptimization
正解：C
解説：
In an adaptive execution plan, the Optimizer makes runtime decisions between nested loop and hash joins using a statistics collector. The collector is a row source that collects statistics about the rows it processes and can adapt the plan based on the number of rows processed.
References:
* Oracle Database SQL Tuning Guide, 19c
質問 # 31
Which two options are part of a Soft Parse operation?
- A. SQL Row Source Generation
- B. Syntax Check
- C. SQL Optimization
- D. Shared Pool Memory Allocation
- E. Semantic Check
正解：E
質問 # 32
You use SQL Tuning Advisor to tune a given SQL statement.
The analysis eventually results in the implementation of a SQL Profile.
You then generate the new SQL Profile plan and enforce it using a SQL PlanBaselinebut forget to disable the SQLProfile and a few days later you find out that the SQL Profile is generating a new execution plan.
Which two statements are true?
- A. The SQL Profiles as well as SQL Plan Baseline are implemented using hints, so they both generate the same plan.
- B. The existence of two concurrent plan stability methods generates a child cursor for every execution.
- C. The execution plan is the one enforced by the SQL Profile.
- D. The SQL Plan Baseline must be accepted in order to be used for the execution plan.
- E. The execution plan is the one enforced by the SQL Plan Baseline.
- F. The conflict between the two plan stability methods results in an error.
正解：C、D
解説：
When both a SQL Profile and a SQL Plan Baseline are in place, the SQL Profile has a stronger preference and the optimizer is more likely to choose the execution plan from the SQL Profile.
C: A SQL Profile is generally more influential than a SQL Plan Baseline because it contains additional statistics and directives that help the optimizer to generate a more efficient execution plan. If both exist, the optimizer will use the profile's plan unless the baseline's plan is proven to be better through the SQL performance monitoring process.
E: SQL Plan Baselines must be accepted before they can be used by the optimizer. If a SQL Plan Baseline is not accepted, it will not be considered for generating the execution plan. Therefore, the presence of an unaccepted SQL Plan Baseline will not automatically force the optimizer to use its plan.
References:
* Oracle Database SQL Tuning Guide, 19c
* Oracle Database Administrator's Guide, 19c
質問 # 33
Users complain about slowness and session interruptions. Additional checks reveal the following error in the application log:
Which file has additional information about this error?
- A. SQL trace file automatically generated by the error
- B. Session trace file SQL trace file automatically generated by the error
- C. ASH report
- D. Alert log
正解：D
解説：
When an ORA-00060 deadlock error occurs, detailed information about the error and the deadlock graph are dumped into the alert log. This log contains a trace file name that you can use to find additional detailed information about the sessions involved in the deadlock and the SQL statements they were executing.
References:
* Oracle Database Administrator's Guide, 19c
* Oracle Database Error Messages, 19c
質問 # 34
You are informed that the RMAN session that is performing the database duplication is much slower than usual. You want to know the approximate time when the rman operation will be completed.
Which view has this information?
- A. V$RMAN_BACKUP_JOB_DETAILS
- B. V$SESSTAT
- C. V$SESSION_LONGOPS
- D. V$SESSION
正解：C
解説：
In Oracle Database, theV$SESSION_LONGOPSview provides insights into various operations within the database that are expected to take more than six seconds to complete. These include operations related to RMAN (Recovery Manager), such as database duplication tasks. This view displays information about the progress of these long-running operations, including the start time, elapsed time, and estimated time to completion.
When an RMAN session is performing a database duplication and is observed to be slower than usual, checking theV$SESSION_LONGOPSview can give an approximation ofwhen the RMAN operation might complete. This view includes fields likeTIME_REMAININGandELAPSED_SECONDSthat help in estimating the completion time of the operation based on its current progress.
References:
* Oracle Database Reference:V$SESSION_LONGOPS
* Oracle Database Backup and Recovery User's Guide:Monitoring RMAN Jobs
質問 # 35
Examine this statement and output:
Which three statements are true?
- A. Session 8779 may be waiting for a user or application response.
- B. Both 9822 and 8779 sessions are waiting for operating system resources.
- C. Session 9857 waited 1354 seconds for another process, which was also waiting for a transaction to end.
- D. Session 8779 may be waiting due to a network problem.
- E. Session 9822 will always stop waiting if the session that owns the TX enqueue issues a COMMIT statement as session 9822 is the first session in the transaction queue.
- F. Session 9857 is not waiting.
正解：A、D、E
解説：
For this SQL statement and output, we can analyze theEVENTcolumn to understand the type of wait:
B: The event "SQL*Net message from client" typically indicates that the session is waiting for a response from the client. This can be due to a network issue, user response, or an application processing delay.
E: The event "SQL*Net message from client" also implies that the session is idle waiting for the client (a user or an application) to send a request to the server. This event usually indicates that the session is not actively working but is instead waiting for the next command.
F: The wait event "enq: TX - row lock contention" suggests that session 9822 is waiting for a row-level lock held by another session. If the holding session issues a COMMIT or ROLLBACK, the lock will be released, and session 9822 will stop waiting. Since this session is experiencing row lock contention, it implies it's waiting for a specific transaction to complete.
References:
* Oracle Database Reference, 19c
* Oracle Wait Events Documentation
質問 # 36
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