Oracle 1z0-083 Exam Dumps & Practice Test Questions
Question No 1:
Which two statements correctly describe the best practices for tuning the performance of an Oracle database? (Choose two.)
A. Leveraging the Oracle Database time model helps pinpoint the database components that require tuning.
B. Performance tuning should stop once users are happy with how the application performs.
C. Tuning should conclude when the system consistently meets its defined service-level objectives.
D. Oracle instance memory tuning must always come before any file system adjustments.
E. SQL tuning must always precede any efforts to optimize the file system.
F. The alert log is the most important tool for identifying performance tuning opportunities.
Correct Answers: A, C
Explanation:
Effective Oracle database performance tuning is a structured, metrics-based process rather than a trial-and-error approach. The correct methodology is rooted in understanding system behavior through diagnostic tools and aligning performance improvements with pre-established business goals.
Option A is correct because the Oracle Database time model is designed to show where processing time is spent within the system, such as during SQL execution, parsing, or I/O operations. This model enables database administrators (DBAs) to prioritize tuning efforts based on measurable data instead of relying on assumptions or user complaints. By identifying performance bottlenecks accurately, tuning efforts can yield faster and more targeted improvements.
Option C is also accurate. The main objective of performance tuning is to ensure that the system fulfills its Service-Level Objectives (SLOs), which are predetermined and agreed upon with stakeholders. These SLOs represent acceptable performance thresholds. Once they are consistently achieved, further tuning becomes unnecessary, even if marginal improvements are possible. Continuing beyond this point can lead to diminishing returns or even destabilize a previously well-functioning system.
The remaining options are less reliable or incorrect.
Option B is problematic because user satisfaction is subjective and not always aligned with actual system performance.
Option D and Option E suggest fixed orders of operations, but tuning priorities depend on the specific bottlenecks identified. There is no universal order for all tuning situations.
Option F overstates the value of the alert log, which is useful for error diagnostics but not designed for detailed performance analysis.
Ultimately, performance tuning is most successful when it is guided by factual data and aligned with operational goals.
Question No 2:
Which two statements correctly describe the functionality of Oracle Flashback technologies? (Choose two.)
A. FLASHBACK QUERY retrieves historical data using redo logs from both online and archived sources.
B. FLASHBACK VERSION QUERY tracks changes over time by referencing redo logs.
C. FLASHBACK TABLE can be used to restore a column that was accidentally dropped.
D. FLASHBACK DROP can restore dependent objects like indexes when a dropped table is recovered.
E. FLASHBACK DATABASE may require redo log application after rollback to ensure database consistency.
Correct Answers: D, E
Explanation:
Oracle Flashback technologies offer sophisticated options for recovering data without resorting to full database restores or downtime. These features are particularly useful for correcting human errors or recovering from logical data corruption.
Option D is correct because FLASHBACK DROP provides the ability to restore a table that was accidentally dropped. This functionality works through the Recycle Bin, where dropped objects are stored temporarily. When a table is recovered using FLASHBACK DROP, all associated dependent objects—such as indexes, triggers, and constraints—are also restored, assuming they were in the Recycle Bin.
Option E is also correct. FLASHBACK DATABASE allows administrators to revert the entire database to a previous state using flashback logs. However, these logs might not contain all the necessary data, especially if the flashback operation spans a long time period or past a restore point. In such scenarios, Oracle may require the application of redo logs (either online or archived) to roll forward changes and bring the database to a transactionally consistent state.
The other options are inaccurate due to common misunderstandings about Flashback's dependencies and scope.
Option A and Option B are incorrect because both FLASHBACK QUERY and FLASHBACK VERSION QUERY use undo data, not redo logs. Undo data helps reconstruct the previous state of data rows or changes made over time, but it is limited by undo retention settings.
Option C is invalid since FLASHBACK TABLE reverts the entire table to a previous state but cannot restore individual columns that were dropped. Such changes would require more invasive recovery methods or table rebuilds.
Oracle Flashback features significantly reduce recovery complexity, enabling DBAs to perform precise, time-efficient corrections with minimal impact on database availability.
Question No 3:
Which three statements correctly describe how application seed pluggable databases (PDBs) behave within Oracle’s Multitenant Architecture? (Choose three.)
A. An application seed PDB is always synchronized with the application root PDB when the application is upgraded.
B. Once an application container exists, you cannot add an application seed PDB to it.
C. After cloning from an application seed PDB, a new application PDB can install an older version of the application.
D. An application seed PDB gets automatically synchronized with the application root PDB when the application is installed.
E. An application seed PDB cannot be removed from its application container.
F. A newly created application PDB cloned from an application seed PDB includes the latest version of the application.
G. An application seed PDB is optional in an application container.
Correct Answers: D, F, G
Explanation:
Oracle Multitenant Architecture introduces application containers and application seed PDBs to simplify the management and deployment of enterprise applications across multiple pluggable databases.
Option D is correct. When an application is installed in the application root PDB, Oracle automatically synchronizes the application seed PDB to include the installed application components. This process ensures that any future application PDBs cloned from the seed will have the baseline application ready without requiring additional setup.
Option F is also accurate. Once a new application PDB is created by cloning the application seed PDB, it immediately contains the most recent version of the application, as defined in the seed. This enables rapid provisioning of fully functional application environments, especially useful for development, testing, or deployment across different business units.
Option G is valid because the presence of an application seed PDB is optional. It is a convenience feature that helps automate and standardize application provisioning but is not a requirement. Administrators can choose to create and use it depending on their architectural needs and workflows.
Other options are incorrect due to misunderstanding the behavior of the synchronization and versioning processes:
Option A is false because automatic synchronization during application upgrades does not occur. Synchronization only happens during installation unless manually triggered.
Option B is incorrect since administrators can add a seed PDB to an existing container.
Option C is wrong because you cannot automatically downgrade an application version during the cloning process.
Option E is false; application seed PDBs can be removed if no longer needed.
Understanding the role and flexibility of application seed PDBs is essential for managing efficient and scalable multitenant environments in Oracle databases.
Question No 4:
Which three statements correctly reflect the roles and default behaviors of the Automatic Workload Repository (AWR), Automatic Database Diagnostic Monitor (ADDM), and the Manageability Monitor (MMON) process in Oracle Database? (Choose three.)
A. ADDM may recommend reducing the buffer cache size under specific workload conditions.
B. ADDM can advise increasing the size of the buffer cache to address memory-related performance issues.
C. By default, MMON initiates the creation of AWR snapshots every 30 minutes.
D. ADDM only runs when explicitly triggered by a database administrator.
E. AWR snapshots are automatically purged after 8 days unless configured otherwise.
F. Oracle requires manual deletion of AWR snapshots once they are outdated.
Correct Answers: B, C, E
Explanation:
Oracle Database includes a set of automated diagnostic tools that enable proactive performance monitoring and tuning. Three central components in this ecosystem are the Automatic Workload Repository (AWR), the Automatic Database Diagnostic Monitor (ADDM), and the Manageability Monitor (MMON) background process.
The Automatic Workload Repository (AWR) collects performance data in the form of snapshots taken at regular intervals. These snapshots serve as a foundation for performance analysis. By default, Oracle creates a new snapshot every 30 minutes, a task handled by the MMON background process. MMON automates this process, ensuring that performance data is continuously collected without manual intervention.
ADDM uses this AWR data to perform automated performance analysis after each snapshot is taken. One of ADDM’s tasks is to assess memory allocation efficiency. If it identifies frequent buffer cache misses or memory-related bottlenecks, it may recommend increasing the size of the buffer cache. However, it does not recommend decreasing it, since reducing memory allocation can negatively impact performance.
Furthermore, Oracle automatically purges old AWR snapshots after a default period of 8 days. This helps maintain database performance and manage storage usage. Manual deletion is unnecessary unless you’re managing space for a custom use case or manually altering retention policies.
Statement A is incorrect because ADDM does not recommend reducing buffer cache size. Statement D is false because ADDM runs automatically after each AWR snapshot. Lastly, Statement F is wrong because snapshot deletion is automatically managed based on retention settings.
Understanding how these components interact helps DBAs effectively use Oracle’s self-managing capabilities, ensuring smooth and proactive database operations.
Question No 5:
Which two statements correctly describe how diagnostic messages and logging behavior are handled during Oracle Recovery Manager (RMAN) backup and recovery operations? (Select two options)
A. Messages related to media management software for SBT (System Backup to Tape) devices are always logged to a dedicated file named sbtio.log.
B. When analyzing RMAN error messages, the error stack should be read starting from the bottom, since errors are listed in reverse chronological order.
C. RMAN errors appear in chronological order, and therefore should be interpreted from the top of the stack downwards.
D. When using the LOG clause in an RMAN command-line session, all output generated during the parsing and execution of commands is directed both to the specified log file and to the standard output (console).
E. The LOG clause in RMAN ensures that output is written only to the log file and not to standard output.
F. Media management-related messages for SBT devices are captured and recorded in Oracle trace files.
Correct Answers: A, B
Explanation:
Oracle Recovery Manager (RMAN) is a robust tool used for backup and recovery operations, and it generates numerous diagnostic messages to assist administrators in troubleshooting issues. Understanding the logging behavior and how to interpret RMAN error messages is vital for effective problem resolution during backup and recovery.
First, when dealing with media management, particularly when using SBT (System Backup to Tape) devices, RMAN logs relevant messages in a dedicated file called sbtio.log. This file captures all communication related to the media management software, which can help administrators pinpoint issues with third-party media systems, such as errors with tape drives or incorrect configurations. These logs are essential for diagnosing hardware or software issues in the backup process.
Second, RMAN error stacks should be interpreted by reading them from the bottom up, as errors are listed in reverse chronological order. The last error (found at the bottom) usually represents the root cause of the problem, and errors above it are typically cascading failures resulting from the initial issue. Reading the error stack this way allows DBAs to identify the primary cause of a failure, rather than wasting time investigating subsequent errors that are symptoms of the first.
While the LOG clause in RMAN commands directs the output to a log file, it does not prevent this information from also being displayed on the console. This enables DBAs to both log and view the output in real-time, aiding quick troubleshooting during command execution. However, this was not part of the correct answers in this case.
Statement C is incorrect, as RMAN errors are listed in reverse order, meaning the most recent error is at the bottom of the stack, not the top. Statement D is also incorrect because the LOG clause writes output to both the log file and standard output, not just the log file. Statement F is misleading, as media management-related messages for SBT devices are stored in sbtio.log, not in Oracle trace files.
Properly interpreting RMAN's diagnostic logs is essential for efficient troubleshooting, ensuring smooth and reliable backup and recovery operations.
Question No 6:
Which three statements accurately describe memory management behaviors in Oracle Database instances regarding allocation and adjustment of memory components? (Choose three.)
A. When using Automatic Shared Memory Management (ASMM), the database can dynamically increase the size of the Large Pool by reducing the size of the Shared Pool.
B. With Automatic Memory Management (AMM), the database instance can increase the size of the System Global Area (SGA) by reducing the size of the Program Global Area (PGA).
C. After restarting the database instance, automatically adjusted SGA components always revert to their original initial sizes.
D. Using Automatic Memory Management (AMM) requires locking the SGA into physical memory.
E. When using Automatic Shared Memory Management (ASMM), the database can increase the size of the PGA by reducing the SGA.
F. Online Transaction Processing (OLTP) systems generally utilize less PGA than Decision Support Systems (DSS).
Correct Answers: A, B, F
Explanation:
In Oracle Database, effective memory management is crucial for optimizing performance and resource utilization. The System Global Area (SGA) and the Program Global Area (PGA) are two critical memory components, with the SGA shared among all database processes and the PGA being private to each server process. Oracle offers various memory management configurations, including Automatic Shared Memory Management (ASMM) and Automatic Memory Management (AMM), to adjust these memory areas dynamically.
First, ASMM allows Oracle to dynamically manage memory within the SGA. When the database requires more memory for certain components, such as the Large Pool, ASMM can reduce memory allocated to other components, such as the Shared Pool, to make room for the larger Large Pool. This dynamic adjustment optimizes memory distribution without requiring manual configuration changes.
Second, AMM provides a more advanced memory management model, where Oracle dynamically adjusts both the SGA and PGA sizes based on workload demands. If the SGA requires more memory, AMM can reduce the PGA size, and vice versa. This flexibility ensures that memory is allocated efficiently based on the workload's needs, improving overall database performance.
Third, OLTP systems generally perform many small, frequent transactions and use less PGA compared to DSS systems, which often involve large, complex queries that demand more memory for sorting and joins. This distinction is due to the different workload characteristics of OLTP and DSS systems, with OLTP typically being more memory-efficient in terms of PGA usage.
Statement C is incorrect because auto-tuned SGA components do not revert to their original sizes after a restart. Instead, they are re-adjusted according to the defined initialization parameters and Oracle’s memory advisor. Statement D is incorrect because locking the SGA into physical memory is not a requirement for AMM. Statement E is false because ASMM does not adjust memory for the PGA, which is managed separately.
Understanding how AMM and ASMM interact with SGA and PGA components enables DBAs to optimize memory allocation effectively, leading to improved database performance and resource utilization.
Question No 7:
Which three of the following statements correctly describe the requirements and behavior of Database Point-in-Time Recovery (PITR) in Oracle?
A. FLASHBACK DATABASE must be enabled in order to perform a Point-in-Time Recovery.
B. The database must be in the MOUNT state when initiating a Point-in-Time Recovery.
C. The Managed Recovery Process (MRP) is used during Database Point-in-Time Recovery.
D. The database must be configured in ARCHIVELOG mode to allow Point-in-Time Recovery.
E. A timestamp or System Change Number (SCN) must be provided to identify the target point for recovery.
F. A RESETLOGS operation is never needed after completing Point-in-Time Recovery.
Correct Answers: B, D, E
Explanation:
Database Point-in-Time Recovery (PITR) is a powerful Oracle feature that allows administrators to restore a database to a specific moment in the past, usually to recover from a logical error such as accidental data deletion or corruption. PITR is typically executed using RMAN (Recovery Manager) and involves the use of backups and archived redo logs.
Option B is correct because the database must be placed in the MOUNT state before initiating PITR. At this stage, the control file is available, but datafiles are not opened for general access, making it possible to apply archived redo logs without modifying the current state of the data.
Option D is also correct. PITR relies heavily on the presence of archived redo logs, which record all transactions. Therefore, the database must be operating in ARCHIVELOG mode, allowing Oracle to keep these logs for recovery purposes.
Option E is correct because when performing PITR, the administrator must define a recovery target—either using a timestamp (e.g., '2025-05-01 09:00:00') or a System Change Number (SCN), which uniquely identifies a point in the transaction history.
Option A is incorrect. Although the FLASHBACK DATABASE feature allows for quick recovery to a prior state, it is not a prerequisite for PITR. PITR can be performed independently using backups and archived logs.
Option C is incorrect. The Managed Recovery Process (MRP) is used in Data Guard environments for standby databases, not in standard PITR scenarios.
Option F is misleading. In most PITR cases, the database must be opened with RESETLOGS to reset the redo log sequence, especially after restoring and recovering to a prior point in time.
In summary, the accurate statements regarding Oracle's Point-in-Time Recovery are B, D, and E.
Question No 8:
Which of the following options is used to perform a point-in-time recovery in Oracle?
A. RMAN (Recovery Manager) backup
B. Flashback Database
C. Data Pump Export/Import
D. Database cloning
Correct Answer: B
Explanation:
In Oracle, Flashback Database is the most commonly used method for performing a point-in-time recovery. Point-in-time recovery allows the database to be restored to a specific point, such as before a failure or corruption occurred, without the need to recover the entire database from backups.
Here's how Flashback Database works:
Flashback uses the Flashback logs (which are stored in the flash recovery area) to rewind the database to a previous point in time.
It allows for undoing changes that have been made, essentially "reversing" the database back in time to a particular timestamp or SCN (System Change Number).
Let's break down the incorrect options:
A (RMAN backup): RMAN can be used for complete or incomplete recovery, but for point-in-time recovery, you would need to restore from backup and apply archived logs or incremental backups to achieve a specific point in time.
C (Data Pump Export/Import): Data Pump is used for moving data between databases (import/export), but it does not perform point-in-time recovery.
D (Database cloning): Cloning is the process of creating an exact copy of a database, but it's not used to recover to a specific point in time.
Thus, Flashback Database (Option B) is the best choice for point-in-time recovery, and it offers a fast and efficient way to recover from logical corruption or accidental data changes without requiring a full restore from backups.
Question No 9:
Which of the following Oracle features enables database administrators to monitor the performance and health of a database in real-time?
A. Oracle Data Guard
B. Oracle Enterprise Manager (OEM)
C. Flashback Query
D. Oracle ASM
Correct Answer: B
Explanation:
Oracle Enterprise Manager (OEM) is the correct answer. OEM is a comprehensive monitoring and management tool for Oracle databases and other Oracle products. It provides real-time monitoring, alerting, and reporting of various aspects of database performance, including memory usage, CPU load, disk I/O, and query execution.
OEM can:
Track performance metrics for database instances.
Alert administrators about potential issues, such as slow queries, resource contention, or hardware failures.
Provide automated diagnostics for common problems and help identify performance bottlenecks.
Let’s look at the incorrect answers:
A (Oracle Data Guard): While Oracle Data Guard is used for database disaster recovery and standby database management, it does not provide real-time performance monitoring.
C (Flashback Query): Flashback Query allows you to view historical data and undo changes, but it doesn't provide real-time monitoring of the database's performance.
D (Oracle ASM): Oracle ASM (Automatic Storage Management) is used for storage management and organizing database files, but it does not provide monitoring or performance management capabilities.
Therefore, Oracle Enterprise Manager (OEM) is the tool most suitable for real-time monitoring and performance analysis.
Question No 10:
In Oracle, what is the primary purpose of the Undo Tablespace?
A. To manage data backups
B. To store undo data to roll back transactions
C. To store redo log data
D. To manage storage for database indexes
Correct Answer: B
Explanation:
The Undo Tablespace plays a crucial role in Oracle database transactions by storing undo data that allows the database to roll back transactions. When a transaction modifies data, the changes are written to the undo tablespace so they can be reversed if the transaction is rolled back.
Here’s a deeper dive:
Undo data is essential for managing the consistency of transactions. If a transaction encounters an error or the user explicitly rolls it back, the undo data in the undo tablespace is used to restore the original state of the data before the transaction was executed.
Undo data is also used to provide read consistency, which ensures that queries will always return consistent results, even if the data is being modified by another transaction.
Let’s review the other options:
A (Data backups): Backups are typically handled by RMAN or the file system, not by the undo tablespace.
C (Redo log data): Redo logs store changes to the database to ensure recoverability in case of a failure, but they are different from undo data, which is used for rollback.
D (Database indexes): Indexes are stored in regular tablespaces, not the undo tablespace.
Thus, the primary purpose of the Undo Tablespace (Option B) is to store undo information for transaction rollback and maintaining consistency in database operations.
These practice questions are designed to test your understanding of critical database administration concepts such as recovery methods, monitoring tools, and transaction management. Preparing with such questions will help you solidify your knowledge for the Oracle 1Z0-083 exam.
