Free Oracle 1z0-915-1 Practice Exam with Questions & Answers

Data loaded into a MySQL HeatWave cluster:

B.Data is partitioned across cluster nodes for scalability: This allows the system to distribute the workload and handle large datasets efficiently. D.Data is stored in hybrid columnarformat to speed up analytic queries: The hybrid columnar format optimizes storage and speeds up query performance, especially for analytic workloads.

Creating a new DB system with data import provides the benefit of faster import with minimal logging. This process is optimized to import large datasets efficiently and quickly, reducing the amount of logging overhead and ensuring a rapid setup of the new DB system.

When restoring the backup of a stand-alone DB system to a new DB system, the following changes are allowed:

Use a different subnet for the new DB system(Answer B): You can select a different subnet within the same VCN or a different VCN for the new DB system, providing flexibility in network configuration.

Use a different shape for the new DB system(Answer C): You can choose a different compute shape for the new DB system, allowing you to scale the compute resources according to the requirements.

References:

OCI MySQL Database Service Backup and Restore Documentation

B.ENGINE=csv SECONDARY_ENGINE=lakehouse ENGINE_ATTRIBUTE=’{"file": [{"region": "us-ashburn-1", "namespace": "mytenant", "bucket": "bucket01", "name": "airport.csv"}] }’: This table option defines a Lakehouse external table based on a CSV file. It specifies thecsvengine for the table and uses thelakehouseas the secondary engine, along with the file's location details in OCI Object Storage.

When automatic backup retention of a DB system is disabled,deleting the DB system(Answer C) will delete all automatic backups of the DB system.

Automatic Backups: These are backups created automatically by the OCI service to ensure data protection.

Backup Deletion: If automatic backups are disabled and you delete the DB system, all associated automatic backups are also deleted. This operation is irreversible, and you should ensure that necessary backups are taken before deleting the DB system.

References:

OCI MySQL Database Service Backup and Restore

To determine the version of MySQL running on your DB system, you can use the following SQL statements:

SELECT @@version;(Answer B): This query retrieves the MySQL server version from the system variables.

SHOW VARIABLES LIKE 'version';(Answer C): This query displays the server version along with other related version variables.

Steps:

Connect to your MySQL DB system.

Execute eitherSELECT @@version;orSHOW VARIABLES LIKE 'version';to retrieve the version information.

References:

MySQL Server Version Information

SHOW VARIABLES Syntax

Initialization variables(Answer A) cannot be modified in MySQL custom configurations. These variables are set at the start of the MySQL service and are not changeable without restarting the service.

Initialization variables are parameters that define how the MySQL server initializes.

Changes to these variables require restarting the MySQL server to take effect.

Examples include variables likeinnodb_buffer_pool_size, which determine memory allocation settings on startup.

References:

MySQL Configuration Variables Documentation

To change the configuration of a high-availability DB system, you must follow these steps:

Stop the DB system: This ensures that the system is in a consistent state and that no transactions are being processed during the configuration change.

Edit the DB system: Make the necessary changes to the configuration.

Change the configuration: Apply the configuration changes.

Start the DB system: Restart the system to apply the new configuration settings.

When exporting data to Object Storage withMySQL Shell util.dumpInstance,you must specifyociParManifest: true(Answer B). This option creates a pre-authenticated request (PAR) manifest file, which allows for secure access and upload to Object Storage without requiring direct credentials.

References:

MySQL Shell Documentation

OCI Object Storage Documentation

Automatic DB system version upgrades in OCI are performed to the next release in sequence. This means that the system is upgraded to the next available version rather than skipping to the most recent release, ensuring a stable and tested upgrade path.