B. Masking or anonymizing sensitive data:

Data privacy regulations (likeGDPR,HIPAA) mandate thatpersonally identifiable information (PII)is protected, even in non-production environments.

Cloning a database without masking sensitive data could expose confidential information to unauthorized users.

Techniques include:

Data masking:Replacing real data with realistic, but non-sensitive values.

Data anonymization:Irreversibly removing personally identifiable information.

Why the other options are incorrect:

A. Matching compute shape:Relevant to performance, not privacy.

C. Using the same database version:Important for compatibility, but not related to data privacy.

D. Same NSG rules:Important for network security, but does not directly address data exposure.

E. Off-peak scheduling:Minimizes disruption but does not address data protection.

Data Access in Key-Value Stores:

A key-value database works by storing data askey-value pairs. The primary access methodinvolves:

Providing aunique keyto quickly retrieve the associated value.

This model is highly efficient forsimple lookupsand data retrieval where thekey is known.

Due to itssimplicity and speed, it is commonly used for caching and session management.

Why the other options are incorrect:

A:SQL queries are used in relational databases, not key-value stores.

C:Traversing nodes is typical ingraph databases.

D:Scanning all documents is inefficient and not the primary method in key-value stores.

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.

Using MySQL Replication for Minimal Downtime:

Replication allows forreal-time synchronizationbetween the source MySQL instance and theHeatWave instance. Once the replication catches up, performing aswitchoverto the HeatWave instance ensures minimal disruption.

This method is especially effective forlarge databases, as data is continuouslysynchronized during the migration process.

The switchover itself incurs minimal downtime as the applications are redirected to the new instance.

Why the other options are incorrect:

A:mysqldump and restore are time-consuming for large datasets.

B:Physical backup and restore are faster than logical, but still involve significant downtime.

D:Direct data file copying is risky and may cause data corruption.

E:ETL processes are typically slow and prone to data consistency issues.

C. Utilizing OCI Database backups:

Integrated withOracle Cloud Infrastructure (OCI), providing consistent and complete backups.

Supports both theMySQL Database System and the HeatWave cluster, ensuring data integrity.

Automates backup scheduling and retention policies.

Facilitates easy restoration in case of data loss or corruption.

Why the other options are incorrect:

A. Manual copying:Prone to errors and lacks consistency.

B. Manual dumps to Object Storage:Labor-intensive and not automated.

D. MySQL replication:Suitable for high availability, but not a substitute for regular backups.

E. MySQL Enterprise Backup on nodes:Complex and not designed for HeatWave's distributed environment.

RCU Calculation:

Read Capacity Units (RCUs) are determined based ondata size (average record size), read frequency (number of reads per second), and consistency level (eventual vs. strong consistency). Complex security roles do not impact the calculation because they do not directly influence the amount of data read or the frequency of access.

Why the other options are correct:

A:Larger record sizes increase RCU requirements.

B:Higher read frequency demands more RCUs.

D:Strong consistency requires more read operations compared to eventual consistency.

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.