Oracle 1z0-084 Dumps

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 Alerts

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 Management

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 theCREATE_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

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

DB time includes the time spent on user and background processes. It can be greater than the elapsed time because it accumulates the active time of all the processes. For example, if two sessions are each active for 2 seconds at the same time, DB time would accumulate 4 seconds, while the elapsed time would be only 2 seconds.References:

• Oracle Database Performance Tuning Guide, 19c
• Oracle Database Reference, 19c

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

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

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

When you enable statistics gathering for a specific service and module usingDBMS_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_STATS

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

When sessions concurrently insert data into a table with an LOB column and one session needs to allocate a new extent because it cannot find available space, the wait event associated with this contention is "enq: HW - contention". The HW stands for High Water Mark which is related to space allocation in the database segment. When asession needs to allocate a new extent, it may raise this wait event in other sessions that are also attempting to allocate space in the same LOB segment.

References

• Oracle Database 19c Reference Guide - enq: HW - contention

Baselines are typically taken during the production phase of the application lifecycle. They provide a snapshot of performance metrics under normal operating conditions which can be used for comparison against future performance. Baselines are essential for understanding how the system performs under its typical workload and for detecting deviations from this expected performance over time, especially after changes like migrations, upgrades, or significant changes in user activity.

References

• Oracle Database 19c Performance Tuning Guide - Managing Performance Through Baselines

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

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

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

To investigate the cause of the ORA-04036 error, which indicates that PGA memory usage exceeds thePGA_AGGREGATE_LIMIT, the appropriate views to consult areDBA_HIST_ACTIVE_SESS_HISTORYandDBA_HIST_PROCESS_MEM_SUMMARY.

• DBA_HIST_ACTIVE_SESS_HISTORY:This view provides historical information about active sessions in the database. It includes details about the SQL executed, the execution context, and the resources consumed by each session. By examining this view, you can identify the specific sessions and SQL queries that were active and potentially consuming excessive PGA memory around the time the ORA-04036 error occurred.
• DBA_HIST_PROCESS_MEM_SUMMARY:This view contains historical summaries of memory usage by processes. It can help in identifying the processes that were consuming a significant amount of PGA memory, leading to the ORA-04036 error. This view provides aggregated memory usage information over time,making it easier to pinpoint the processes responsible for high PGA memory consumption.

Together, these views offer a comprehensive overview of the memory usage patterns and specific queries or processes that might have contributed to exceeding thePGA_AGGREGATE_LIMIT, resulting in the ORA-04036 error.

References:

• Oracle Database Reference:DBA_HIST_ACTIVE_SESS_HISTORY
• Oracle Database Reference:DBA_HIST_PROCESS_MEM_SUMMARY
• Oracle Database Performance Tuning Guide:Managing Memory