1z0-915-1 MySQL HeatWave Implementation Associate Rel 1 Questions and Answers

When creating a new DB system with data import, the following conditions apply:

The data must be stored in an Object Storage bucket in the same OCI region as the new DB system(Answer C): This ensures that the data is readily accessible and can be efficiently imported into the new DB system.

A valid pre-authenticated request must be provided to access the data(Answer D): This allows secure access to the data stored in the Object Storage bucket without needing to handle credentials directly.

References:

OCI Object Storage Documentation

Pre-Authenticated Requests Documentation

To determine whether a query is offloaded to the HeatWave cluster for execution,check the value of therapid_query_offload_countglobal status variable(Answer B).

rapid_query_offload_count: This variable indicates the number of queries that have been offloaded to the HeatWave cluster. By checking its value before and after running the query, you can determine if the query was offloaded.

Steps:

Connect to the MySQL DB system.

RunSHOW GLOBAL STATUS LIKE 'rapid_query_offload_count';before and after executing the query to see if the count increases, indicating offloading.

References:

MySQL HeatWave Documentation

Monitoring HeatWave Status Variables

The error message indicates that the source has purged required binary logs, making it impossible to replicate the missing transactions. This happens when the administrator manually deletes binary log files from the source DB system, or the binary log expiration period is too short, causing automatic purging before the replica can fetch the transactions.

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

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

To minimize DB system downtime caused by automatic maintenance operations, you should enable high availability. High availability ensures that there are multiple instances of your database running in different fault domains or availability domains, reducing the impact of maintenance on the system's availability.

A query may not be offloaded to the HeatWave cluster for execution due to the following reasons:

A.Theuse_secondary_enginesession variable is OFF: This setting controls whether queries should be offloaded to the secondary engine (HeatWave). B.The client is connected to the DB system instead of the HeatWave cluster: For queries to be offloaded, the client must be connected to the HeatWave cluster. E.A required column is excluded from the RAPID secondary engine: If a necessary column is not available in the HeatWave (RAPID) secondary engine, the query cannot be offloaded.

To prepare data for a new DB system with data import in OCI, you shouldexport the data into an Object Storage bucket with a MySQL Shell dump utility(Answer B). This method allows you to store the data in a scalable and durable object storage service before importing it into the new DB system.

Steps:

Use MySQL Shell dump utility to export the data.

Save the export files to an Object Storage bucket in OCI.

Import the data from the Object Storage bucket into the new DB system.

References:

MySQL Shell Documentation

OCI Object Storage Documentation

You can determine the uptime of a DB system bychecking the DB system details in the OCI Web console(Answer B). The console provides information on the system status, including the uptime since the last start.

Steps:

Log in to the OCI Web console.

Navigate to the MySQL DB system.

View the details page of the DB system, where the uptime information is displayed.

References:

OCI Console Documentation

Monitoring DB System Uptime

To speed up the data load into a DB system usingMySQL Shell util.loadDump(), you can use thedeferTableIndexes: alloption (Answer D). This option defers the creation of indexes until after the data has been loaded, which can significantly improve the speed of the loading process.

Steps:

Export your data using MySQL Shell dump utility.

Useutil.loadDump()to import the data and specify thedeferTableIndexes: alloption.

The data is loaded without building indexes initially, reducing the time required for the import.

After the data load is complete, indexes are created in a batch process, which is more efficient than creating them during the data load.

References:

MySQL Shell Dump & Load Documentation

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

A.Reduce query latency: By distributing read queries across multiple replicas, the load on the primary instance is reduced, which can decrease query latency. D.Scale read queries: Read replicas allow scaling of read operations by providing additional instances to handle read queries, improving overall performance and throughput.

You can stop a MySQL DB system using the following methods:

A.Use the STOP action on the DB system details page in the OCI Console: This is a straightforward way to stop the DB system via the Oracle Cloud Infrastructure web interface. D.Execute themysql db-system stopcommand from OCI CLI: This command uses the Oracle Cloud Infrastructure Command Line Interface to stop the DB system programmatically.

When training a classification model with MySQL HeatWave AutoML, the following requirements must be met:

The target column and all feature columns must be stored in a single table(Answer B): All data necessary for training the model should be in one table to simplify the data processing and training pipeline.

The target column must have at least two distinct values(Answer E): For classification tasks, the target column must have multiple distinct values to enable the model to differentiate between classes.

References:

MySQL HeatWave AutoML Documentation

MySQL HeatWave User Guide

A.You can set a value for any global MySQL variable in a configuration: MySQL HeatWave allows you to configure and set global MySQL variables to optimize performance and customize the environment as needed.

C.You can view custom configuration sets with the OCI CLIoci mysql db-system getcommand: The OCI CLI provides commands to retrieve details about MySQL DB systems, including custom configurations.

To create a connection in Database Tools to use the SQL Worksheet feature, the following steps are required:

Create an OCI password(Answer A): This password is necessary for authentication when connecting to the MySQL DB system.

Create an OCI secret(Answer D): Secrets are used to store sensitive information like passwords securely. The secret will contain the database credentials.

Import an X.509 certificate into the OCI vault(Answer E): This certificate is required for secure connections to the database, ensuring encrypted communication.

References:

OCI Database Tools Documentation

Using OCI Secrets

X.509 Certificates Documentation