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Title: [Q12-Q32] 1z1-084 Certification Exam Dumps Questions in here [Jan-2025]

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 1z1-084 Certification Exam Dumps Questions in here [Jan-2025]
Updated 1z1-084 Exam Practice Test Questions


NEW QUESTION 12SGA_TARGET and PGA_AGGREGATE_TARGET are configured to nonzero values.MEMORY_target is then set to a nonzero value but memory_MAX_TARGET is not set.Which two statements are true?
 
 
 
 
 
 
 
When MEMORY_TARGET is set to a nonzero value, Oracle automatically manages the memory allocation between the System Global Area (SGA) and the Program Global Area(PGA). If MEMORY_MAX_TARGET is not explicitly set, Oracle will behave in the following manner:* MEMORY_MAX_TARGET will default to the value of MEMORY_TARGET, assuming the platform allows for the value of MEMORY_TARGET to be increased dynamically. This means that MEMORY_TARGET represents both the initial allocation and the maximum limit for the dynamically managed memory unless MEMORY_MAX_TARGET is specified differently.* If MEMORY_TARGET is set to a value that is less than the sum of the current values of SGA_TARGET and PGA_AGGREGATE_TARGET, Oracle will use the higher sum as the default value for MEMORY_MAX_TARGET to ensure that there is adequate memory for both areas. The database instance will not start if MEMORY_TARGET is not sufficient to accommodate the combined SGA and PGA requirements.References* Oracle Database Administrator’s Guide 19c: Automatic Memory Management* Oracle Database Performance Tuning Guide 19c: Using Automatic Memory ManagementNEW QUESTION 13Examine this statement and output:Which two situations can trigger this error?
 The user lacks the required privileges to execute the DBMS WORKLOAD CAPTURE package or the directory.
 There is a file in the capture directory.
 The syntax is incomplete.
 The capture directory is part of the root file system.
 The instance is unable to access the capture directory.
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, 19cNEW QUESTION 14Which three statements are true about server-generated alerts?
 They are notifications from the Oracle Database Server of an existing or impending problem.
 They provide notifications but never any suggestions for correcting the identified problems.
 They are logged in the alert log.
 They can be viewed only from the Cloud Control Database home page.
 Their threshold settings can be modified by using DBMS_SERVER_ALERT.
 They may contain suggestions for correcting the identified problems.
Server-generated alerts in Oracle Database are designed to notify DBAs and other administrators about issues within the database environment. These alerts can be triggered by a variety of conditions, including threshold-based metrics and specific events such as ORA- error messages. Here’s how these options align with the statements provided:* A (True):Server-generated alerts are indeed notifications from the Oracle Database Server that highlight existing or impending issues. These alerts are part of Oracle’s proactive management capabilities, designed to inform administrators about potential problems before they escalate.* C (True):These alerts are logged in the alert log of the Oracle Database. The alert log is a crucial diagnostic tool that records major events and changes in the database, including server-generated alerts.This log is often the first place DBAs look when troubleshooting database issues.* F (True):Server-generated alerts may include suggestions for correcting identified problems. Oracle Database often provides actionable advice within these alerts to assist in resolving issues more efficiently. These suggestions can range from adjusting configuration parameters to performing specific maintenance tasks.Options B, D, and E do not accurately describe server-generated alerts:* B (False):While the statement might have been true in some contexts, Oracle’s server-generated alerts often include corrective suggestions, making this statement incorrect.* D (False):Server-generated alerts can be viewed from various interfaces, not just the Cloud Control Database home page. They are accessible through Enterprise Manager, SQL Developer, and directly within the database alert log, among other tools.* E (False):While it’s true that threshold settings for some alerts can be modified, the method specified, usingDBMS_SERVER_ALERT, is not correct. Threshold settings are typically adjusted through Enterprise Manager or by modifying specific initialization parameters directly.References:* Oracle Database Documentation:Oracle Database 19c: Performance Management and Tuning* Oracle Base: Alert Log and Trace Files* Oracle Support:Understanding and Managing Server-Generated AlertsNEW QUESTION 15Which two statements are true about disabling Automatic Shared Memory Management (ASMM)?
 All auto-tuned SGA components are reset to their original user-defined values.
 All SGA components excluding fixed SGA and other internal allocations are readjusted immediately after disabling ASMM.
 Both SGA_TARGET and SGA_MAX_SIZE must be set to zero.
 All SGA components retain their current sizes at the time of disabling.
 The SGA size remains unaffected after disabling ASMM.
 It requires a database instance restart to take effect.
When ASMM is disabled, the sizes of the automatically managed SGA components remain at their current values. ASMM is controlled by theSGA_TARGETparameter. IfSGA_TARGETis set to a non-zero value, ASMM is enabled and Oracle will automatically manage the sizes of the various SGA components. When ASMM is disabled, by settingSGA_TARGETto zero, the SGA components that were automatically sized will retain their current sizes rather than being reset to their original user-defined values. The overall size of the SGA remains the same unless manually changed by modifying individual component sizes or SGA_MAX_SIZE.References:* Oracle Database Administration Guide, 19c* Oracle Database Performance Tuning Guide, 19cNEW QUESTION 16For which two actions can SQL Performance Analyzer be used to assess the impact of changes to SQL performance?
 storage, network, and interconnect changes
 operating system upgrades
 changes to database initialization parameters
 database consolidation for pluggable databases (PDBs)
 operating system and hardware migrations
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, 19cNEW QUESTION 17You need to collect and aggregate statistics for the ACCTG service and PAYROLL module, and execute:Where do you find the output of this command?
 By viewing V$SERV_MOD_ACT_STATS
 In $ORACLE_BASE/diag/rdbms/<db unique name>/<instance name>/trace
 By viewing V$SERVICE_STATS
 In the current working directory
When you enable statistics gathering for a specific service and module using DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE, the output is aggregated and can be viewed using theV$SERV_MOD_ACT_STATSdynamic performance view. This view contains the cumulative statistics of database activity broken down by service and module, which is exactly what you collect when executing the provided command.* B (Incorrect):While many types of trace files are located in the Diagnostic Destination directory ($ORACLE_BASE/diag), the aggregated statistics for services and modules are not written to trace files but are instead viewable through dynamic performance views.* C (Incorrect):TheV$SERVICE_STATSview provides service-level statistics but does not provide the* combined service/module-level breakdown.* D (Incorrect):The output of the PL/SQL block is not written to a file in the current working directory; it is stored in the data dictionary and accessible via dynamic performance views.References:* Oracle Database PL/SQL Packages and Types Reference:DBMS_MONITOR* Oracle Database Reference:V$SERV_MOD_ACT_STATSNEW QUESTION 18Which two statements are true about the use and monitoring of Buffer Cache Hit ratios and their value in tuning Database I/O performance?
 A 99% cache hit ratio can be observed for database instances which have very poor I/O performance.
 A 60% cache hit ratio can be observed for database instances which have very good I/O performance.
 The performance of workloads that primarily generate full table scans and fast full index scans are always affected by the cache hit ratio.
 The buffer cache advisory view v$db_cache_advice provides advice on cache hit ratios appropriate for the instance workload.
 Both the RECYCLE and KEEP buffer caches should always have a very high cache hit ratio.
NEW QUESTION 19Which two statements are true about the use and monitoring of Buffer Cache Hit ratios and their value in tuning Database I/O performance?
 The performance of workloads that primarily generate full table scans and fast full index scans are always affected by the cache hit ratio.
 A 99% cache hit ratio can be observed for database instances which have very poor I/O performance.
 The buffer cache advisory view v$db_cache_advice provides advice on cache hit ratios appropriate for the instance workload.
 Both the RECYCLE and KEEP buffer caches should always have a very high cache hit ratio.
 A 60% cache hit ratio can be observed for database instances which have very good I/O performance.
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_adviceNEW QUESTION 20Which two statements are true about Data Pump import for objects that used the in Memory (IM) column store in their source database?
 It always gives preference to the IM column store clause defined at the tablespace level over table-level definitions.
 It must always transports existing INMEMORY attributes.
 Its INMEM0RY_CLAUSE of the Data Pump Export allows modifications to IM column store clause of a table with existing INMEMORY setting.
 Its TRANSFORM clause can be used to add the INMEMORV clause to exported tables that lack them.
 It ignores the IM column store clause of the exporting objects.
 It can generates the INMEMORY clause that matches the table settings at export time.
When importing objects that used the In-Memory (IM) column store in their source database using Oracle Data Pump, the following statements are true:* D (Correct):TheTRANSFORMclause can be used to alter object creation DDL during import operations. This can include adding theINMEMORYclause to tables that were not originally using the IM column store.* F (Correct):The import operation can preserve theINMEMORYattributes of tables as they were at the time of export, effectively replicating the IM column store settings from the source database.The other statements are not accurate in the context of Data Pump import:* A (Incorrect):Data Pump does not give preference to the IM column store clauses at the tablespace level over table-level definitions unless explicitly specified by theTRANSFORMclause.* B (Incorrect):While Data Pump can transport existingINMEMORYattributes, it is not mandatory. It is controlled by theINCLUDEorEXCLUDEData Pump parameters or theTRANSFORMclause.* C (Incorrect):TheINMEMORY_CLAUSEparameter is not part of the Data Pump Export utility. To modify the IM column store clauses, you would use theTRANSFORMparameter during import, not export.* E (Incorrect):Data Pump does not ignore the IM column store clause unless specifically instructed to do so via theEXCLUDEparameter.References:* Oracle Database Utilities:Data Pump Export* Oracle Database Utilities:Data Pump ImportNEW QUESTION 21Examine this output of a query of VSPGA_TAPGET_ADVICE:Which statements is true’
 With a target of 700 MB or more, all multipass executions work areas would be eliminated.
 PGAA_AGGREGATE should be set to at least 800 MB.
 GGREGATE_TARGET should be set to at least 700 MB.
 With a target of 800 MB or more, all one-pass execution work areas would be eliminated.
The V$PGA_TARGET_ADVICE view provides advice on potential performance improvements by adjusting the PGA_AGGREGATE_TARGET parameter. The column ESTD_OVERALLOC_COUNT indicates the estimated number of work areas that would perform multiple passes if the PGA_AGGREGATE_TARGET were set to the size in the TARGET_MB column.A: According to the output, at the target of 700 MB, the ESTD_OVERALLOC_COUNT is 30. This suggests that if PGA_AGGREGATE_TARGET is set to 700 MB, 30 multipass execution work areas would be required. If we look further down, at the target of 800 MB, the ESTD_OVERALLOC_COUNT is 0, indicating that increasing PGA_AGGREGATE_TARGET to 800 MB or more would eliminate the need for multipass executions, not at 700 MB as initially suggested by the option. Hence, the verified answer derived from the data is slightly nuanced; it should be 800 MB to eliminate all multipass executions.References:* Oracle Database Performance Tuning Guide, 19c* Oracle Database Reference, 19cNEW QUESTION 22Examine this AWR report excerpt:You must reduce the impact of database I/O, without increasing buffer cache size and without modifying the SQL statements.Which compression option satisfies this requirement?
 MN STORE COMPRESS FOR QUERY LOW
 STORE COMPRESS
 ROW STORE COMPRESS ADVANCED
 COLUMN STORE COMPRESS FOR QUERY HIGH
The question asks to reduce database I/O impact without increasing the buffer cache size or modifying SQL statements. This indicates a need to reduce the physical I/O required to access the data. Let’s analyze the scenario and the options.Analysis of the AWR Report:* Top Wait Events:* The top foreground wait event is db file sequential read, which accounts for 40.4% of DB time.This indicates significant physical I/O operations, primarily single-block reads, which are typically associated with index access.* Reducing the physical I/O associated with db file sequential read can significantly improve performance.* SQL Ordered by Reads:* The SQL consuming the most reads involves high physical I/O. This confirms the need to reduce I/O overhead by compressing data efficiently to minimize physical reads.Compression Techniques and Their Suitability:* A. COLUMN STORE COMPRESS FOR QUERY LOW:* This option is a columnar compression method that optimizes for query performance but provides less compression compared to the HIGH option. While effective, it is not as suitable as FOR QUERY HIGH for reducing I/O.* B. STORE COMPRESS:* This is the basic compression option for tables and does not offer the advanced capabilities required for reducing significant physical I/O for queries.* C. ROW STORE COMPRESS ADVANCED:* This is a row-level compression that is suitable for OLTP workloads. While it reduces storage, it does not reduce query-related I/O as effectively as columnar compression.* D. COLUMN STORE COMPRESS FOR QUERY HIGH (Correct Option):* This is the most effective option for reducing query-related I/O. It:* Uses columnar compression to reduce the size of data stored on disk.* Reduces the number of physical reads by compressing data highly, meaning fewer blocks need to be read.* Optimizes query performance for analytical workloads, which aligns with the scenario described in the AWR report.Why COLUMN STORE COMPRESS FOR QUERY HIGH Is the Best Fit:* It is designed to improve query performance by minimizing the amount of I/O required.* Suitable for environments with heavy read operations (as indicated by the db file sequential read waits).* Does not require changes to SQL or buffer cache size, adhering to the constraints in the question.Reference to Oracle Documentation:* Oracle Database 19c Performance Tuning Guide:* Section: Using Compression to Reduce Storage and I/O Requirements.* Discussion of columnar compression techniques for reducing I/O in query-intensive environments.* Oracle Advanced Compression Documentation:* Details on COLUMN STORE COMPRESS FOR QUERY HIGH and its benefits for analytical workloads.NEW QUESTION 23You 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?
 recommendations regarding the creation of additional indexes
 recommendations regarding rewriting the SQL statements
 recommendations regarding the creation of materialized views
 recommendations regarding the creation of SQL Patches
 recommendations regarding partitioning the tables
https://docs.oracle.com/en/database/oracle/oracle-database/21/tgsql/sql-tuning-advisor.html#GUID-8E1A39CB-A491-4254-8B31-9B1DF7B52AA1The goal is to reduce the db file scattered read waits, which are associated with full table scans. These are I/O operations where Oracle retrieves data blocks scattered across the disk, typically when large amounts of data are read inefficiently. Running the SQL Tuning Advisor analyzes the workload and provides tuning recommendations. Let’s evaluate the options.Why A. Recommendations regarding the creation of additional indexes is correct:* Full table scans (which cause db file scattered read) often occur because suitable indexes are missing.* The SQL Tuning Advisor can identify queries that would benefit from indexes and recommend creating them. Indexes allow the database to access data more efficiently using row lookups, reducing the need for full table scans.Why B. Recommendations regarding rewriting the SQL statements is correct:* Sometimes, poorly written SQL statements cause inefficient execution plans that lead to db file scattered read.* SQL Tuning Advisor can recommend SQL rewrites to make better use of indexes, avoid full table scans, or optimize joins. For example:* Rewriting predicates to use indexed columns.* Using hints to guide the optimizer.Why Other Options Are Incorrect:* C. Recommendations regarding the creation of materialized views:* Materialized views are typically recommended to optimize complex queries involving aggregations or joins, not to address db file scattered read directly. They are less relevant for solving I/O issues caused by full table scans in this context.* D. Recommendations regarding the creation of SQL Patches:* SQL Patches are used to influence the execution plan for specific SQL statements. While SQL Patches can potentially fix performance issues, the SQL Tuning Advisor focuses on improving SQL and database design rather than patching queries.* E. Recommendations regarding partitioning the tables:* Partitioning tables can improve query performance, especially for very large datasets. However, this is a database design-level recommendation and is not typically provided by SQL Tuning Advisor. Partitioning would not directly target db file scattered read.How SQL Tuning Advisor Helps:The SQL Tuning Advisor provides actionable recommendations, such as:* Creating indexes to reduce full table scans.* Rewriting SQL to optimize the execution plan.* Improving statistics to help the optimizer make better decisions.References to Oracle Documentation:* Oracle Database 19c Performance Tuning Guide:* Section: Using SQL Tuning Advisor to Optimize Workloads.* Explains recommendations for indexes and SQL rewrites to reduce I/O.* Understanding Wait Events:* Details about db file scattered read and how to address it.NEW QUESTION 24You need to transport performance data from a Standard Edition to an Enterprise Edition database. What is the recommended method to do this?
 Export the data by using expdp from Statspack and import it by using $ORACLE_HOME/rdbms/admin/awrload into the AWR repository.
 Export the data by using expdp from the ftatspack repository and import it by using impdp into the AWR repository.
 Export the data by using the expdp utility and parameter file spuexp.par from the Statspack repository and import it by using impdp into Export the data by using expdp from the Statspack repository and import it by using impdp into the AWR repository.
 Export the data by using the exp utility and parameter file spuexp.par from the Statspack repository and import it by using imp into a dedicated Statspack schema on the destination.
To transport performance data from an Oracle Database Standard Edition, which uses Statspack, to an Enterprise Edition database, which uses AWR, you must consider the compatibility of data structures and repository schemas between these tools. The recommended method is:* D (Correct): Export the data using the exp utility with a parameter file appropriate for Statspack (like spuexp.par) from the Statspack repository and import it into a dedicated Statspack schema on the destination. Since Statspack and AWR use different schemas, it’s not recommended to import Statspack data directly into the AWR repository.The other options are incorrect because:* A (Incorrect): expdp is not designed to export from Statspack, and awrload is intended for loading from an AWR export file, not a Statspack export.* B (Incorrect): Although expdp and impdp are used for exporting and importing data, the AWR repository schema is different from the Statspack schema, so importing Statspack data directly into the AWR repository is not recommended.* C (Incorrect): Using expdp to export from Statspack and then importing directly into the AWR repository is not the correct approach due to the schema differences between Statspack and AWR.References:* Oracle Database Performance Tuning Guide: Migrating from Statspack to AWRNEW QUESTION 25Accessing the SALES tables causes excessive db file sequential read wait events.Examine this AWR except:Now, examine these attributes displayed by querying dba_tables:Finally, examine these parameter settings:Which two must both be used to reduce these excessive waits?
 Partition the SALES table.
 Increase PCTFREE for the SALES table.
 Re-create the SALES table.
 Compress the SALES table.
 Coalesce all sales table indexes.
The AWR excerpt points to excessive physical reads on the SALES table and index, suggesting the need for optimizing table storage and access.Partitioning the SALES table (A) can reduce ‘db file sequential read’ waits by breaking down the large SALES table into smaller, more manageable pieces. This can localize the data and reduce the I/O necessary for query operations.Compressing the SALES table (D) can also help reduce I/O by minimizing the amount of data that needs to be read from disk. This can also improve cache utilization and reduce the ‘db file sequential read’ waits.References:* Oracle Database VLDB and Partitioning Guide, 19c* Oracle Database Administrator’s Guide, 19cThese changes are recommended based on Oracle’s best practices for managing large tables and reducing I/O waits, ensuring better performance and efficiency.NEW QUESTION 26Which two options are part of a Soft Parse operation?
 SQL Row Source Generation
 SQL Optimization
 Semantic Check
 Shared Pool Memory Allocation
 Syntax Check
NEW QUESTION 27You need to collect and aggregate statistics for the ACCTG service and PAYROLL module, and execute:Where do you find the output of this command?
 By viewing V$SERV_MOD_ACT_STATS
 In $ORACLE_BASE/diag/rdbms/<db unique name>/<instance name>/trace
 By viewing V$SERVICE_STATS
 In the current working directory
When you enable statistics gathering for a specific service and module using DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE, the output is aggregated and can be viewed using the V$SERV_MOD_ACT_STATS dynamic performance view. This view contains the cumulative statistics of database activity broken down by service and module, which is exactly what you collect when executing the provided command.* B (Incorrect): While many types of trace files are located in the Diagnostic Destination directory ($ORACLE_BASE/diag), the aggregated statistics for services and modules are not written to trace files but are instead viewable through dynamic performance views.* C (Incorrect): The V$SERVICE_STATS view provides service-level statistics but does not provide the combined service/module-level breakdown.* D (Incorrect): The output of the PL/SQL block is not written to a file in the current working directory; it is stored in the data dictionary and accessible via dynamic performance views.References:* Oracle Database PL/SQL Packages and Types Reference: DBMS_MONITOR* Oracle Database Reference: V$SERV_MOD_ACT_STATSNEW QUESTION 28SGA_TARGET and PGA_AGGREGATE_TARGET are configured to nonzero values.MEMORY_target is then set to a nonzero value but memory_MAX_TARGET is not set.Which two statements are true?
 
 
 
 
 
 
 
When MEMORY_TARGET is set to a nonzero value, Oracle automatically manages the memory allocation between the System Global Area (SGA) and the Program Global Area (PGA). If MEMORY_MAX_TARGET is not explicitly set, Oracle will behave in the following manner:* MEMORY_MAX_TARGET will default to the value of MEMORY_TARGET, assuming the platform allows for the value of MEMORY_TARGET to be increased dynamically. This means that MEMORY_TARGET represents both the initial allocation and the maximum limit for the dynamically managed memory unless MEMORY_MAX_TARGET is specified differently.* If MEMORY_TARGET is set to a value that is less than the sum of the current values of SGA_TARGET and PGA_AGGREGATE_TARGET, Oracle will use the higher sum as the default value for MEMORY_MAX_TARGET to ensure that there is adequate memory for both areas. The database instance will not start if MEMORY_TARGET is not sufficient to accommodate the combined SGA and PGA requirements.References* Oracle Database Administrator’s Guide 19c: Automatic Memory Management* Oracle Database Performance Tuning Guide 19c: Using Automatic Memory ManagementNEW QUESTION 29Database 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?
 Re-create the SALES table sorted in order of index IX_SALES_TIME_ID.
 Re-create index IX_SALES_TIME_ID using ADVANCED COMPRESSION.
 Re-create the SALES table using the columns in IX_SALES_TIME_ID as the hash partitioning key.
 Partition index IX_SALES_TIME_ID using hash partitioning.
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 CompressionNEW QUESTION 30Accessing the SALES tables causes excessive db file sequential read wait events.Examine this AWR except:Now, examine these attributes displayed by querying dba_tables:Finally, examine these parameter settings:Which two must both be used to reduce these excessive waits?
 Partition the SALES table.
 Increase PCTFREE for the SALES table.
 Re-create the SALES table.
 Compress the SALES table.
 Coalesce all sales table indexes.
The AWR excerpt points to excessive physical reads on the SALES table and index, suggesting the need for optimizing table storage and access.Partitioning the SALES table (A) can reduce ‘db file sequential read’ waits by breaking down the large SALES table into smaller, more manageable pieces. This can localize the data and reduce the I/O necessary for query operations.Compressing the SALES table (D) can also help reduce I/O by minimizing the amount of data that needs to be read from disk. This can also improve cache utilization and reduce the ‘db file sequential read’ waits.References:* Oracle Database VLDB and Partitioning Guide, 19c* Oracle Database Administrator’s Guide, 19cThese changes are recommended based on Oracle’s best practices for managing large tables and reducing I/O waits, ensuring better performance and efficiency.NEW QUESTION 31Which three statements are true about tuning dimensions and details of v$sys_time_model and DB time?
 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.
 Systems in which CPU time is dominant need more tuning that those in which WAIT TIME is dominant.
 The proportion of WAIT TIME to CPU TIME always increases with increased system load.
 When WAIT TIME is high, instance tuning may improve performance.
 Parse Time Elapsed accounts for successful soft and hard parse operations only.
 DB Time accounts for all time used by background processes and user sessions.
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, 19cNEW QUESTION 32Examine this statement and its corresponding execution plan:Which phase introduces the CONCATENATION step?
 SQL Semantic Check
 SQL Execution
 SQL Row Source Generation
 SQL Transformation
 SQL Adaptive Execution
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 Loading …






	
	


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