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Oracle Database Performance Tuning Tools, covers a range of Oracle database performance and tuning tools such as SQL*Plus, SQL Developer, Enterprise Manager, and many others. Finally, the fourth section, Performance Tuning and Troubleshooting, deals with database performance issues and their resolution, including SQL tuning, Instance tuning, and tuning the Oracle Network.

Oracle 1Z0-084 Certification Exam is a comprehensive and challenging exam that tests the knowledge and skills of database professionals in the area of performance and tuning management. Passing 1Z0-084 exam can lead to career advancement opportunities, higher salaries, and the ability to demonstrate expertise in this critical area of database management.

 

NEW QUESTION # 21
Examine these commands, which execute successfully:

Which statement is true?

• A. AD DM is enabled for all pluggable databases.
• B. AWR- snapshots in all pluggable databases will be purgedautomatically after every 60 mins.
• C. ADDM, AWR, and ASH reports can be purged automatically.
• D. AWR snapshots can be purged manually in pluggable databases.

Answer: D

Explanation:
TheDBMS_WORKLOAD_REPOSITORY.MODIFY_SNAPSHOT_SETTINGSprocedure allows setting attributes related to AWR snapshots. While the interval setting controls the frequency of snapshot generation, purging them is a separate process that can be managed either automatically (with retention settings) or manually.References:
* Oracle Database PL/SQL Packages and Types Reference, 19c
* Oracle Multitenant Administrator's Guide, 19c

NEW QUESTION # 22
An Oracle 19c database uses default values for all optimizer initialization parameters.
After a table undergoes partition maintenance, a large number of wait events occur for:
cursor: pin S wait on X
Which command reduces the number of these wait events?

• A. ALTER SYSTEM SET SESSION CACHED CURSORS = 500;
• B. ALTER SYSTEM SET CURSOR_INVALIDATION = DEFERRED;
• C. ALTER SYSTEM SET CURSOR_SPACE_FOR_TIME - TRUE;
• D. ALTER SYSTEM SET CURSOR_SHARING = FORCE;

Answer: B

Explanation:
Thecursor: pin S wait on Xwait event suggests contention for a cursor pin, which is associated with mutexes (a type of locking mechanism) that protect the library cache to prevent concurrent modifications. This issue can often be alleviated by deferring the invalidation of cursors until the end of the call to reduce contention.
The correct command to use would be:
* C (Correct):ALTER SYSTEM SET CURSOR_INVALIDATION=DEFERRED;This setting defers the invalidation of dependent cursors until the end of the PL/SQL call, which can reduce thecursor: pin S wait on Xwait events.
The other options are incorrect in addressing this issue:
* A (Incorrect):SettingCURSOR_SHARINGtoFORCEmakes the optimizer replace literal values with bind variables. It doesn't address the contention for cursor pins directly.
* B (Incorrect):CURSOR_SPACE_FOR_TIME=TRUEaims to reduce the parsing effort by keeping cursors for prepared statements open. It may increase memory usage but does not directly resolve cursor: pin S wait on Xwaits.
* D (Incorrect):IncreasingSESSION_CACHED_CURSORScaches more session cursors but doesn't necessarily prevent the contention indicated by thecursor: pin S wait on Xwait events.
References:
* Oracle Database Reference:CURSOR_INVALIDATION
* Oracle Database Performance Tuning Guide:Reducing Cursor Invalidation

NEW QUESTION # 23
Which three types of statistics are captured by statspack with snap level 6?

• A. Optimizer execution plans
• B. Segment-level statistics
• C. Plan usage data
• D. Parent and child latches
• E. Enqueue statistics
• F. Parent and child latches

Answer: B,E,F

Explanation:
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

NEW QUESTION # 24
Examine this statement and output:

Which two situations can trigger this error?

• A. The syntax is incomplete.
• B. The user lacks the required privileges to execute the DBMS WORKLOAD CAPTURE package or the directory.
• C. The instance is unable to access the capture directory.
• D. The capture directory is part of the root file system.
• E. There is a file in the capture directory.

Answer: B,C

Explanation:
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

NEW QUESTION # 25
Which two options are part of a Soft Parse operation?

• A. SQL Row Source Generation
• B. Syntax Check
• C. Semantic Check
• D. Shared Pool Memory Allocation
• E. SQL Optimization

Answer: C

NEW QUESTION # 26
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 sorted in order of index IX_SALES_TIME_ID.
• B. Re-create index IX_SALES_TIME_ID using ADVANCED COMPRESSION.
• C. Re-create the SALES table using the columns in IX_SALES_TIME_ID as the hash partitioning key.
• D. Partition index IX_SALES_TIME_ID using hash partitioning.

Answer: B

Explanation:
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

NEW QUESTION # 27
Which two actions can cause invalidation or loss of one or more results in the SQL Query Result Cache?

• A. A request was made by the RCBG background process in a physical standby database that is opened read only and whose primary has a result cache.
• B. A request was made by the RCBG background of a non-RAC database.
• C. result_cache_max_size is set dynamically to 0.
• D. One or more results were aged out of the result cache.
• E. Decreasing the value set for RESULT_CACHE_REMOTE_EXPIRATION.

Answer: C,D

Explanation:
The SQL Query Result Cache stores the results of queries and PL/SQL function calls for reuse. However, entries in the result cache can be invalidated or lost under certain conditions:
A: Results can be aged out of the cache when the cache becomes full and new results need to be stored. This process ensures that the cache does not exceed its allocated memory and that it contains the most recently used entries.
B: Setting theRESULT_CACHE_MAX_SIZEparameter to 0 will effectively disable the result cache and all cached results will be lost, as Oracle will no longer allocate any memory to the result cache.
References:
* Oracle Database Performance Tuning Guide, 19c

NEW QUESTION # 28
Which three statements are true about tuning dimensions and details of v$sys_time_model and DB time?

• A. The proportion of WAIT TIME to CPU TIME always increases with increased system load.
• B. DB Time accounts for all time used by background processes and user sessions.
• C. Systems in which CPU time is dominant need more tuning that those in which WAIT TIME is dominant.
• D. Statspack cannot account for high CPU time when CPU TIME is a Top 10 event in DB time. When CPU time is high, SQL tuning may improve performance.
• E. Parse Time Elapsed accounts for successful soft and hard parse operations only.
• F. When WAIT TIME is high, instance tuning may improve performance.

Answer: B,D,F

Explanation:
A: Statspack is a performance diagnostic tool that can help identify high CPU usage issues. High CPU time may indicate that SQL statements need to be tuned for better performance.
D: High wait times can often be reduced by instance tuning, such as adjusting database parameters or improving I/O performance.
F: DB Time is a cumulative time metric that includes the time spent by both user sessions and background processes executing database calls.References:
* Oracle Database Performance Tuning Guide, 19c
* Oracle Database Concepts, 19c

NEW QUESTION # 29
You execute the following:
EXECUTE DBMS_AuTO_TASK_ADMIN.DISABLE;
Which advisor remains enabled?

• A. Automatic SQL Tuning
• B. SQL Plan Management Evolve Advisor
• C. Automatic Optimizer Statistics Collection
• D. Automatic Segment Advisor
• E. Optimizer Statistics Advisor

Answer: C

Explanation:
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

NEW QUESTION # 30
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. index full scan
• B. db file sequential read
• C. index range scan
• D. db file scattered read

Answer: B

Explanation:
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

NEW QUESTION # 31
Examine this statement and its corresponding execution plan:

Which phase introduces the CONCATENATION step?

• A. SQL Row Source Generation
• B. SQL Execution
• C. SQL Adaptive Execution
• D. SQL Semantic Check
• E. SQL Transformation

Answer: E

Explanation:
The CONCATENATION step in an execution plan is introduced during the SQL Transformation phase. This phase is part of the optimizer's query transformations which can include various techniques to rewrite the query for more efficient execution. The CONCATENATION operation is used to combine the results of two separate SQL operations, typically when there is an OR condition in the WHERE clause, as seen in the provided query.
References:
* Oracle Database SQL Tuning Guide, 19c
* Oracle Database Concepts, 19c

NEW QUESTION # 32
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 rewriting the SQL statements
• D. recommendations regarding the creation of materialized views
• E. recommendations regarding partitioning the tables

Answer: A,D

Explanation:
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

NEW QUESTION # 33
18. The application provider has given full indications regarding the procedure to collect statistics.
To reduce the space used in the SYSAUX tablespace, you want to prevent the optimizer statistics Advisor from running.
Which method will allow you to do this?

• A. Set the AUTO_STATS_ADVISOR_TASK global statistics preference to FALSE.
• B. Use DBMS STATS.DROP ADVISOR TASK to drop the AUTO_STATS_ADVISOR_TASK task.
• C. Use DBMS_AUTO_TASK_ADMIN. DISABLE to disable the AUTO_STATS_ADVISOR_TASK task.
• D. Set the parameter OPTIMIZER_ADAPTIVE_STATISTICS to FALSE.

Answer: C

Explanation:
The Oracle Optimizer statistics advisor, which is part of the automated tasks framework, can be disabled using the DBMS_AUTO_TASK_ADMIN package. This will prevent it fromrunning and thus reduce space usage in the SYSAUX tablespace.References:
* Oracle Database PL/SQL Packages and Types Reference, 19c

NEW QUESTION # 34
Examine this command:

What is the maximum number of baselines generated by this command that you can have at any given time?

• A. 0
• B. 1
• C. 2
• D. 3

Answer: A

Explanation:
TheDBMS_WORKLOAD_REPOSITORY.CREATE_BASELINE_TEMPLATEprocedure is used to create a repeating baseline template in the Automatic Workload Repository (AWR). This template will generate baselines for a specified duration of time on a repeating schedule. Theparameters of the CREATE_BASELINE_TEMPLATEprocedure include the start and end times, as well as the day of the week and hour in the day when the baseline should be captured.
Given that the command specifies a repeating baseline every Monday at 5 PM with a duration of 3 hours and it expires after 30 days, the number of baselines generated by this command that you can have at any given time depends on how many Mondays fall within the most recent 30-day period.
Since the maximum number of Mondays that can occur within any 30-day period is 5 (four to five weeks), but considering the baseline has a duration of 3 hours and starts every Monday at 5 PM, only one baseline for each Monday can exist at a time. However, since baselines are preserved for 30 days, you could have multiple instances of Monday baselines preserved at a time.
* A (Incorrect):There can be more than one baseline at a time because the template will generate a baseline for every Monday during the 30-day expiration period.
* B (Incorrect):There will be more than three baselines because the template creates a baseline for every Monday within the 30-day expiration period.
* C (Correct):Over a 30-day period, considering the duration of the baselines and their frequency, you could have up to a maximum of 52 baselines if you consider the entire year.
* D (Incorrect):There is no option that restricts the number of baselines to 5 specifically, the answer relies on the calculation of how many baselines can exist over a period of time considering their expiration.
References:
* Oracle Database PL/SQL Packages and Types Reference:DBMS_WORKLOAD_REPOSITORY

NEW QUESTION # 35
What are the least elevated values of statistics_level and C0NTR0LJ4ANAGEMENT_PACK_ACCESS that allow the usage of Monitoring of Database Operations?

• A. STATISTICS_LEVEL=TYPICAL and CONTROL_MANAGEMENT_PACK_ACCESS=DIAGOSTIC
• B. STATISTICS_LEVEL=BASIC and CONTROL_MANAGEMENT_PACK ACCESS=DIAGOSTIC
• C. STATISTICS_LEVEL=ALL and
  CONTROL_MANAGEMENT_PACK_ACCESS=DIAGOSTIC+TUNING
• D. STATISTICS_LEVEL=TYPICAL and
  CONTROL_MANAGEMENT_PACK_ACCESS-DIAGOSTIC*TUNING

Answer: C

Explanation:
Monitoring of Database Operations requires that theSTATISTICS_LEVELparameter be set toALLand CONTROL_MANAGEMENT_PACK_ACCESSbe set toDIAGNOSTIC+TUNING. These settings enable all the advisory features and automatic tuning features within the Oracle Database, including the Automatic Workload Repository (AWR), Automatic Database Diagnostic Monitor (ADDM), and the full functionality of the SQL Tuning Advisor and SQL Access Advisor, which are components of the Diagnostic and Tuning packs.
* STATISTICS_LEVEL=ALL:This setting enables the collection of all system statistics for problem detection and self-tuning purposes.
* CONTROL_MANAGEMENT_PACK_ACCESS=DIAGNOSTIC+TUNING:This grants access to both the Diagnostic Pack and the Tuning Pack, which are essential for detailed performance monitoring and tuning capabilities.
References:
* Oracle Database Reference:STATISTICS_LEVEL
* Oracle Database Licensing Information User Manual:Oracle Database Management Packs

NEW QUESTION # 36
You must configure and enable Database Smart Flash Cache for a database.
You configure these flash devices:

Examine these parameter settings:

What must be configured so that the database uses these devices for the Database Smart Flash Cache?

• A. Set DB_FLASH_CACHE_SIZE to 192G and MEMORY_TARGET to 256G.
• B. Set DB_FLASH_CACHE_SIZE parameter to 128G, 64G.
• C. Disable Automatic Memory Management and set SGA_TARGET to 256G.
• D. Set DB_FLASH_CACHE_SIZE parameter to 192G.
• E. Set DB_FLASH_CACHE_SIZE to 256G and change device /dev/sdk to 128G.

Answer: B

Explanation:
To configure and enable Database Smart Flash Cache, you must set the DB_FLASH_CACHE_SIZE parameter to reflect the combined size of the flash devices youintend to use for the cache. In this scenario, two flash devices are configured: /dev/sdj with 128G and /dev/sdk with 64G.
* Determine the combined size of the flash devices intended for the Database Smart Flash Cache. In this case, it's 128G + 64G = 192G.
* However, Oracle documentation suggests setting DB_FLASH_CACHE_SIZE to the exact sizes of the individual devices, separated by a comma when multiple devices are used.
* Modify the parameter in the database initialization file (init.ora or spfile.ora) or using an ALTER SYSTEM command. Here's the command for altering the system setting:
ALTER SYSTEM SET DB_FLASH_CACHE_SIZE='128G,64G' SCOPE=SPFILE;
* Since this is a static parameter, a database restart is required for the changes to take effect.
* Upon database startup, it will allocate the Database Smart Flash Cache using the provided sizes for the specified devices.
It is important to note that MEMORY_TARGET and MEMORY_MAX_TARGET parameters should be configured independently of DB_FLASH_CACHE_SIZE. They control the Oracle memory management for the SGA and PGA, and do not directly correlate with the flash cache configuration.
References
* Oracle Database 19c Documentation on Database Smart Flash Cache
* Oracle Support Articles and Community Discussions on DB_FLASH_CACHE_SIZE Configuration

NEW QUESTION # 37
Which two Oracle Database features use database services?

• A. Oracle SQL Tuning Advisor
• B. Database Resource Manager
• C. Oracle Automatic Reoptimization
• D. Oracle Scheduler
• E. Oracle SQL Performance Management

Answer: B,D

Explanation:
Database services in Oracle are used to manage how resources are allocated and how workloads are managed within the database. The features that use database services are:
* B (Correct):Database Resource Manager (DBRM) uses services to control resource allocation to different workloads. It ensures that resources are assigned to the most critical tasks first, based on the service associated with the workload.
* E (Correct):Oracle Scheduler can also utilize database services. Jobs in Oracle Scheduler can be assigned to different services to control resource allocation and prioritization.
The other features mentioned are related to SQL performance but do not directly utilize database services in the way Resource Manager and Scheduler do:
* A:Oracle Automatic Reoptimization is a feature that allows the database to automatically improve the execution plan of a SQL statement after it is executed, based on the actual performance metrics, but it does not directly use database services.
* C:Oracle SQL Performance Management involves various components of SQL tuning and monitoring, but it does not use database services to operate.
* D:Oracle SQL Tuning Advisor provides advice on how to tune SQL queries for better performance.
While it can be used in conjunction with services for managing and analyzing workloads, it doesn't use services in its core functionality.
References:
* Oracle Database Administrator's Guide:Administering Services
* Oracle Database Administrator's Guide:Managing Resources with Oracle Database Resource Manager
* Oracle Database Scheduler Developer's Guide:Using the Scheduler

NEW QUESTION # 38
For which two actions can SQL Performance Analyzer be used to assess the impact of changes to SQL performance?

• A. changes to database initialization parameters
• B. database consolidation for pluggable databases (PDBs)
• C. storage, network, and interconnect changes
• D. operating system upgrades
• E. operating system and hardware migrations

Answer: A,B

Explanation:
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

NEW QUESTION # 39
You must produce a consolidated formatted trace file by combining all trace files generated by all clients for a single service.
Which combination of utilities does this?

• A. Autotrace and TKPROF
• B. Trace Analyzer and Tracsess
• C. Trcsess and TKPROF
• D. TKPROF and Trace Analyzer

Answer: C

Explanation:
To produce a consolidated formatted trace file from multiple trace files generated by all clients for a single service, the combination oftrcsessandTKPROFutilities is used. Thetrcsessutility consolidates trace files based on specified criteria such as session, client identifier, or service name. This results in a single trace file that combines the desired tracing information. Next,TKPROFis used to format the output of the trace file generated bytrcsess, providing a readable summary of the trace, including execution counts, execution times, and SQL statement text along with execution plans.
Steps:
* Usetrcsessto combine trace files:
* Command:trcsess output=consolidated.trc service=your_service_name *.trc
* UseTKPROFto format the consolidated trace file:
* Command:tkprof consolidated.trc output.txt explain=user/password sys=no sort=prsela,fchela References:
* Oracle Database Performance Tuning Guide, 19c
* Oracle Database Utilities, 19c

NEW QUESTION # 40
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 rewriting the SQL statements
• D. recommendations regarding the creation of materialized views
• E. recommendations regarding partitioning the tables

Answer: A,D

Explanation:
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

NEW QUESTION # 41
Which two statements are true about the use and monitoring of Buffer Cache Hit ratios and their value in tuning Database I/O performance?

• A. A 60% cache hit ratio can be observed for database instances which have very good I/O performance.
• B. The performance of workloads that primarily generate full table scans and fast full index scans are always affected by the cache hit ratio.
• C. A 99% cache hit ratio can be observed for database instances which have very poor I/O performance.
• D. Both the RECYCLE and KEEP buffer caches should always have a very high cache hit ratio.
• E. The buffer cache advisory view v$db_cache_advice provides advice on cache hit ratios appropriate for the instance workload.

Answer: C,E

Explanation:
A high buffer cache hit ratio typically indicates that the database is effectively using the buffer cache and does not often need to read data from disk. However, this metric alone is not a reliable indicator of the I/O performance of the database for several reasons:
* Full table scans and fast full index scans (A) can bypass the buffer cache by design if the blocks are not
* deemed reusable shortly, which can impact the cache hit ratio.
* A high cache hit ratio (B) can be misleading if the database performance is poor due to other factors, such as inefficient queries or contention issues.
* The buffer cache advisory (C) is a more valuable tool for understanding the potential impact of different cache sizes on the database's I/O performance. It simulates scenarios with different cache sizes and provides a more targeted recommendation.
* The RECYCLE and KEEP buffer caches (D) are specialized caches designed for certain scenarios.
While high hit ratios can be beneficial, they are not universally required; some workloads might not be significantly impacted by lower hit ratios in these caches.
* A lower cache hit ratio (E) does not necessarily mean poor I/O performance. In some cases, a system with a well-designed storage subsystem and efficient queries might perform well even with a lower cache hit ratio.
References
* Oracle Database 19c Performance Tuning Guide - Buffer Cache Hit Ratio
* Oracle Database 19c Performance Tuning Guide - v$db_cache_advice

NEW QUESTION # 42
......

Oracle 1Z0-084 exam is designed to test the skills of database administrators in managing and optimizing the performance of Oracle Database 19c. Oracle Database 19c Performance and Tuning Management certification validates the knowledge and expertise of professionals in the field of database performance and tuning management. 1Z0-084 exam also serves as a prerequisite for the Oracle Certified Expert, Oracle Database 19c: Performance Tuning certification.

 

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