1z0-1093-25 Sample Questions Answers

Backup Retention Policy:

When aBaseDB system is terminated, automatic backups are not immediately deleted. Instead, they remain stored inOCI Object Storagefor the duration specified by thebackup retention policythat was configured at the time of database creation.

This approach ensures that data can be recovered even after the database instance itself is terminated.

Administrators can manually delete backups if they are no longer needed, but they arenot automatically purged.

Why the other options are incorrect:

A:Backups are not deleted instantly upon termination.

B:All backups are retained as per the policy, not just the most recent.

D:No automatic migration to archive tier occurs.

E:Backup retention settings are defined during provisioning, but not dynamically configurable after termination.

B. VCN and Subnets:Exadata Database Service VM Clusters require a VCN to provide network connectivity for database instances, client access, and backups. Proper subnets are essential for this network setup.

E. Exadata Infrastructure Resource:Before creating a VM Cluster, an Exadata Infrastructure resource must be provisioned. The VM Cluster resides within this infrastructure.

Why the other options are incorrect:

A:OCI Vault and Key are used for encryption but not mandatory for VM Cluster creation.

C:A valid SI is needed for support but not a technical requirement for VM cluster creation.

D:Exadata Cloud@Customer is a separate service from Exadata Database Service.

C. Intelligent Storage Capabilities:

The Exadata Storage Server Software enhances data processing at the storage layer.

Key features include:

Smart Scan:Offloads SQL processing to storage.

Compression:Reduces data size and improves I/O efficiency.

Encryption:Protects data at rest.

This software significantly boosts database performance by reducing data transfer to the compute nodes.

Why the other options are incorrect:

A. VM management:Handled by OCI infrastructure.

B. OS and management software:Not related to Exadata Storage Server Software.

D. Load balancing:Handled by Oracle RAC or OCI load balancers.

Database Software Upgrade:

When upgrading theOracle Database software versionon aBaseDB VM, a newOracle Homeis created to house the upgraded software. Once the database is moved to this new home, the process isnot easily reversible.

Rolling back would requiredowngrading, which is a complex and risky process.

The new Oracle Home ensures that the upgraded database environment isisolated from the previous version, preventing compatibility conflicts.

Why the other options are incorrect:

A:Grid Infrastructure upgrades can be managed independently of the database upgrade.

B:Scaling VMs is a reversible operation.

D:OS patches do not impact the Oracle Home directly.

E:ASM configuration changes are reversible.

C. OCI Monitoring with HeatWave specific metrics:

OCI Monitoring collects and visualizes detailed metrics related to HeatWave cluster operations.

Key metrics include:

Data load throughput

Data load latency

Memory and CPU utilization

These metrics help identify bottlenecks during data loading, allowing for proactive performance tuning.

Integrates withOCI Alarmsto notify administrators when thresholds are breached.

Why the other options are incorrect:

A. OCI Notifications:Sends alerts but does not collect performance metrics.

B. OCI Service Connector Hub:Moves data between services but does not provide direct performance insights.

D. OCI Streaming:Used for real-time data ingestion, not specifically for HeatWave monitoring.

E. OCI Functions:Executes serverless functions, not related to HeatWave metrics.

A. cellcli alter iormplan database dbname shares=value

CellCLI Utility:

cellcli is a command-line interface used to manage Exadata storage cells.

Thealtercommand is used to modify existing configurations, including IORM plans.

IORM (I/O Resource Management):

Helps control how I/O resources are allocated among databases.

Thesharesparameter adjusts the relative priority of I/O requests.

Correct syntax for adjusting IORM:

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cellcli -e "alter iormplan database dbname shares=value"

Why the other options are incorrect:

B. configure iormplan:Used for creating or setting up new IORM plans, not for modification.

C. modify iormplan:modify is not a valid command in CellCLI for IORM.

D. change iormplan:No such command exists in CellCLI.

A. Service Gateway for Oracle Services:

Ensures the HeatWave DB System can accessOracle Serviceslike Object Storage without using the public internet.

Essential for tasks such aspatching and backups.

C. Ingress security rules:

Allows necessary traffic to reach the HeatWave DB System.

Typically, rules will permitMySQL port (3306)and anyapplication-specific ports.

Configured usingVCN security lists or NSGs.

Why the other options are incorrect:

B. Public subnet deployment:Exposes the database to the internet, which is a security risk.

D. Dynamic routing gateway:Not mandatory unless inter-VCN connectivity is specifically required.

E. Blocking egress entirely:Restricting all outbound traffic can prevent necessary updates and communication with Oracle services.

B. Relational vs. NoSQL data relationships:

Relational Databases:Useforeign keysto establish relationships between tables, maintainingreferential integrity.

NoSQL Databases:Typically do not enforce relationships through foreign keys. Instead, they:

Embed related datawithin a single document (common in document stores like MongoDB).

Useapplication-level joinsto link related data (common in key-value or column-family stores).

Graph databases (a type of NoSQL) useedgesto explicitly represent relationships between nodes.

This difference highlights theflexibility vs. consistencytrade-off between NoSQL and relational databases.

Why the other options are incorrect:

A. NoSQL databases lack relationships:Incorrect; they handle relationships differently.

C. NoSQL using foreign keys exclusively:NoSQL databases generally do not enforce such relationships.

D. Relational databases lack relationship mechanisms:Incorrect as relational databases are designed around relationships.

C. Unnecessary cost expenditure:

In Oracle NoSQL Database Cloud Service, you pay for the provisioned RCUs regardless of actual usage.

Consistently underutilized RCUs mean that you are incurring costs without fully utilizing the allocated resources.

Proper capacity planning is crucial to optimize costs.

To reduce expenses, monitor utilization and adjust RCUs accordingly.

Why the other options are incorrect:

A. Improved query performance:While having adequate RCUs prevents throttling, over-provisioning does not inherently enhance performance.

B. Increased storage efficiency:Storage is independent of RCUs, which relate to read throughput.

D. Reduced data durability:Durability is not impacted by underutilized read capacity.

Rate Limiting in NoSQL:

In Oracle NoSQL Database Cloud Service, rate limiting primarily controlsread and write throughput. This means defining themaximum number of read and write operations per secondthat a table can handle.

The goal is toprevent a single table from consuming excessive resources, ensuringfair allocationand system stability.

Why the other options are incorrect:

A:Storage capacity is managed via quotas, not rate limits.

C:CPU and memory are related to system resources, not table operations.

D:Indexing and query complexity are managed differently, often via query optimization.

A. CPU utilization of the compute instances hosting the database:

Autoscaling in NoSQL Database Cloud Service primarily focuses onRCUs (Read Capacity Units)andWCUs (Write Capacity Units).

The objective is to dynamically adjust capacity based onquery workload, not onCPU utilization.

Even if CPU usage is high, it might not necessarily indicate that the capacity units are inadequate.

Why the other options are more relevant:

B. Rejected read requests (RCUs):Direct indicator that read capacity is insufficient, requiring scaling.

C. Rejected write requests (WCUs):Indicates that the write throughput is inadequate, necessitating scaling.

D. Latency of read and write operations:Increased latency often points to under-provisioned throughput.

Understanding Throughput in NoSQL:

Throughput in NoSQL databases is influenced by factors likequery complexity, workload type (read/write), and record size.

Higher query complexity (A):Complex queries involving aggregation or joins consume more read capacity.

Write-heavy workload (B):Writes inherently require more capacity units due to data modification and consistency checks.

Larger record sizes (D):More data per operation increases the read/write capacity needed.

Why C is incorrect:

C:Table scans involve reading large volumes of data, which increases throughput requirements rather than reducing them. Frequent table scans can overwhelm the system, especially with large datasets.

HeatWave's Columnar Processing:

HeatWave improves OLAP performance by storing data in acolumnar formatin memory. This format is particularly efficient foranalytical queriesbecause:

It minimizes the amount of data read by only scanning thenecessary columns.

Columnar storage supportsvectorized processing, which significantly speeds up aggregation operations.

Beingin-memory, it eliminates disk I/O bottlenecks, crucial for high-speed analytics.

Why the other options are incorrect:

A:Indexing is useful, but columnar storage is the primary driver of speed.

C:Caching improves access times but does not address the fundamental OLAP challenge of processing large datasets.

D:HeatWave distributes workload usingparallel processing, not simple sharding.

E:AI-powered indexing is not a core feature of HeatWave.

A. MySQL Query Optimizer:

TheMySQL Query Optimizerdetermines whether a query can benefit from HeatWave’s in-memory, columnar processing.

If a query is deemed suitable, it is automatically offloaded to the HeatWave cluster.

This process significantly improves the execution speed of complex analytical queries.

Why the other options are incorrect:

B. HeatWave AutoPilot:Manages workload optimization but does not directly offload queries.

C. MySQL Router:Manages connection routing, not query offloading.

D. MySQL Shell:Primarily used for administrative tasks, not query optimization.

E. OCI Load Balancer:Manages network traffic distribution, unrelated to database query processing.

Responsibility of DBA:

Before upgrading the Oracle Database software on aBaseDB VM system, the DBA must verify that theunderlying operating system versionis compatible with the new database software version. This is crucial because Oracle Database upgrades may introduce new requirements or dependencies.

The DBA needs to check theOracle Database Upgrade Guideand theOracle Validated Configurationsto ensure compatibility. Upgrading without this validation could lead to compatibility issues, failed upgrades, or reduced performance.

Why the other options are incorrect:

A:OCI manages the infrastructure, but the DBA must ensure compatibility.

C:While OCI manages the OS patching, ensuring compatibility is still a DBA responsibility.

D:OS updates should be addressed before the database upgrade, not afterward.

Super Columns in Column-Family Databases:

Asuper columnis a higher-level construct used incolumn-family NoSQL databases(like Apache Cassandra). It groups related columns together under a single name, forming atwo-level hierarchywithin a column family.

This structure is useful when storing data that naturally fits anested or hierarchical format.

For example, a user profile might contain super columns like "Address" (with sub-columns like "Street", "City", "ZIP") and "Contacts" (with sub-columns like "Phone", "Email").

Why the other options are incorrect:

A:A regular column represents a single value associated with a row key.

C:Primary keys are defined at the row level, not using super columns.

D:While BLOBs can be stored, the primary role of a super column is togroup related columns, not store binary data.

C. Using Oracle Data Guard for a switchover operation:

Aswitchoveris a planned role reversal between the primary and standby databases.

Zero data loss:Since both databases are synchronized, it minimizes downtime.

Ideal for planned maintenance:The primary database is switched to the standby, allowing maintenance on the original primary without downtime.

Data Guard Switchover:

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ALTER DATABASE SWITCHOVER TO standby_db;

Why the other options are incorrect:

A. Full backup with RMAN:Backup does not ensure availability during maintenance.

B. In-place upgrade:Typically involves downtime.

D. Quarterly patch:Patching often requires database restarts, causing downtime.

E. Resizing block volume:Does not maintain availability if the database requires restarting.

Tagging in Database Management:

Tags in Oracle Cloud Infrastructure are essential fororganizing and managing resources.

Grouping Databases (A):Tags allow databases to be grouped logically, simplifying management and performance analysis.

Filtering and Searching (C):Tags make it easier to find specific databases within theDatabase Management console, improving efficiency in large environments.

Why the other options are incorrect:

B:Tags do not propagate automatically; they must be configured properly.

D:Tags are actively used in Database Management for organizing and filtering.

D. Dropping the entire table:

Deleting a table is adestructive operationthat permanently removes the data.

Requires the highest level of permissions due to the potential fordata lossand disruption.

Usually restricted toadministrators or highly privileged users.

Why the other options are incorrect:

A. Simple read operation:Basic permission, often granted to most users.

B. Inserting a row:Requires write permissions, but not as critical as table deletion.

C. Updating a row:Similar to insertion, modifies existing data but does not destroy the table.

D. The database version:

Thedatabase versionis not configurable through the Database Management Service.

The version is determined during the database instance provisioning and is independent of the management service.

The management service can monitor and manage databases of various versions, but it does not control or alter the version itself.

Why the other options are configurable:

A. Frequency of metric collection:Can be adjusted to balance performance and data granularity.

B. Specific metrics collected:Can be customized based on monitoring requirements.

C. Storage space for metrics:Some configurations allow defining the retention and storage capacity for collected data.

A. Secure Communication Channel:

The Oracle Management Agent acts as a bridge between theDatabase Management Serviceand the database.

Enables secure data collection, monitoring, and performance analysis.

Uses encryption to protect data during transmission.

Facilitates monitoring, alerting, and management through OCI services.

Why the other options are incorrect:

B. Backup and recovery operations:These are typically handled by backup tools, not the management agent.

C. OS management:The agent does not manage the operating system itself.

D. Patching and upgrades:While it can assist, it is not specifically designed for patch management.

HeatWave as a Query Accelerator:

HeatWave enhances theMySQL Database Serviceby providing anin-memory, massively parallel query accelerator. It is specifically designed to speed upanalytical (OLAP) queries, making them run significantly faster compared to using MySQL alone.

The system stores data in acolumnar formatand processes it in memory, utilizingdistributed, parallel processingto achieve high performance.

Unlike traditional MySQL setups, HeatWave canexecute complex analytical workloadsefficiently.

Why the other options are incorrect:

A:HeatWave is not a standalone database but an extension of MySQL.

C:It is optimized foranalytical workloads, not transactional.

D:It is more than just a caching layer; it actively processes queries.

E:HeatWave clusters do not split MySQL instances but enhance query processing.

VCN Requirement:

AVirtual Cloud Network (VCN)is essential for creating a BaseDB VM instance because itprovidesnetwork connectivityandIP addressing. Subnets and security rules define the access policies and network segmentation.

Without a VCN, the VM instance cannot communicate with other resources or external networks.

Why the other options are incorrect:

A:Data Guard can be configured after provisioning.

B:Backup policies are important but can be set up later.

D:Oracle GoldenGate replication is optional and not required at the time of provisioning.

B. Optimizing schema and indexes:

Efficient schema design reduces the number of read/write operations.

Proper indexing reduces the need to scan large data volumes, minimizing the number of read capacity units (RCUs) consumed.

This proactive approach helps stay within the provisioned rate limits, avoiding throttling.

Why the other options are incorrect:

A. Increasing storage capacity:Does not address the rate of operations, only storage volume.

C. Disabling encryption:Unwise due to security risks and does not significantly impact rate limits.

D. Consolidating data into one table:Likely increases the rate of operations, worsening the problem.

Performance Hub Real-Time SQL Monitoring:

ThePerformance Hubin Oracle Database Management provides detailed real-time monitoring of SQL queries, including:

Physical Reads (A):Measures the number of physical I/O operations performed by a SQL statement.

Average Active Sessions (B):Reflects the number of sessions actively performing database operations, giving insights into workload and bottlenecks.

These metrics help database administratorsanalyze query performanceand detect issues in real-time.

Why the other options are incorrect:

C:Number of CPUs is a hardware metric, not part of SQL monitoring.

D:Database version is static information, not a performance metric.

Direct Control in BaseDB VM:

In aBaseDB VM deployment, users haveroot-level access to the operating systemand can directly manage the database configuration. This contrasts withAutonomous Database, where Oracle handles most administrative tasks, including patching and resource scaling.

BaseDB VM offersflexibility for custom configurationsand control overOS-level operations.

This is particularly useful for environments requiringcustom scripts, configurations, or database tuning.

Why the other options are incorrect:

A:Autonomous Database features automatic patching, not BaseDB VM.

B:Exadata infrastructure is typically associated withAutonomous Databaserather than VM-based BaseDB.

D:Automatic scaling is a feature of Autonomous Database, not BaseDB.