DS0-001 Online Practice Questions and Answers

Correct Answer: A

The best way for the administrator to accomplish this task is to create a materialized view. A materialized view is a type of view that stores the result of a query on one or more tables as a separate table in the database. A materialized view can aggregate data from multiple tables in a way that does not impact the original tables, and then provide this information to a department as a single source of truth. A materialized view also improves query performance and efficiency by reducing the need to recompute complex queries every time they are executed. The other options are either not suitable or not optimal for this task. For example, creating indexes on those tables may improve query performance on individual tables, but not on aggregated data; creating a new database may require additional resources and maintenance, and may introduce inconsistency or redundancy; creating a function may require additional coding and execution, and may not store the result as a separate table. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.2 Given a scenario, create database objects using scripting and programming languages.

Correct Answer: D

The correct answer is D. When undo management with temporary undo is enabled, the undo data is stored in the temporary tablespace instead of the undo tablespace. The temporary tablespace is a tablespace that stores temporary data such as sort results or intermediate query results. The undo data is the data that records the changes made by transactions on the database. Undo data is used to roll back transactions in case of errors or failures, or to provide read consistency for concurrent queries. By storing undo data in the temporary tablespace, the database can reduce the space consumption and contention in the undo tablespace, and improve performance and scalability. The other options are either incorrect or irrelevant for this question. For example, the system global area is a memory area that stores information shared by all sessions connected to an instance; the undo tablespace is a tablespace that stores undodata by default; the SYSAUX tablespace is a tablespace that stores auxiliary information for various database features. References: CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.1 Given a scenario, perform common database maintenance tasks.

Correct Answer: D

The join that is most appropriate for the analyst to use to create this database view is option D. This join uses the LEFT JOIN clause to combine the client table and the invoice table based on the matching values in the Key column. The WHERE clause filters out the rows where the Invoice.Key column is not null, meaning that the client has made a purchase. The result is a view that shows only the clients who have not made any purchases yet. The other options either do not produce the desired result or have syntax errors. For example, option A would show only the clients who have made purchases, option B would show only the invoices that do not have a matching client, and option C would show all the clients regardless of their purchase status. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.2 Given a scenario, execute database tasks using scripting and programming languages.

Correct Answer: C

The correct order of the steps in the database deployment process is option C. This order follows the best practices for deploying a database system, which are:

Confirm prerequisites: Check the system requirements and compatibility of the database software and tools before installation.

Install: Install the database software and tools on the target server or platform. Configure: Configure the database settings and parameters according to the specifications and needs of the application or organization. Connect: Connect the

database to the network and other systems or applications that will access it.

Test: Test the functionality and performance of the database system and verify that it meets the expectations and requirements.

Validate: Validate the data quality and integrity of the database system and ensure that it complies with the standards and regulations. Release: Release the database system to production and make it available for use by end-users or

customers. The other options do not follow this order and may result in errors, inefficiencies, or security issues. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.1 Given a scenario, install and

configure database software and tools.

Correct Answer: B

The deployment phase in which a DBA ensures the most recent patches are applied to the new database is upgrading. Upgrading is a process that updates an existing database system or software to a newer version or release that may include new features, enhancements, bug fixes, security patches, etc. Upgrading helps improve the performance, functionality, compatibility, and security of the database system or software. Upgrading can be done manually or automatically using tools or scripts provided by the vendor or developer. Upgrading can also involve testing, backup, migration, or rollback procedures to ensure the quality and reliability of the new version or release. The other options are either different deployment phases or not related to deployment at all. For example, importing is a process that transfers data from one source to another using files or formats; provisioning is a process that allocates resources such as servers, storage, network, etc., for a system or software; modifying is a process that changes existing data or objects in a database using commands or scripts. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.3 Given a scenario, update database systems.

Correct Answer: A

The SQL command that the administrator should use to ensure that records from the two tables are not duplicated is option A. This command uses the UNION clause to combine the records from the legacy table and the newer table into a

single result set. The UNION clause also eliminates any duplicate records that may exist in both tables, and sorts the result by default. The other options either do not produce the desired result or have syntax errors. For example, option B

would join the records from the two tables based on a common column, but not remove any duplicates; option C would return only the records that are common to both tables, but not the ones that are unique to each table; option D would

produce a Cartesian product of the records from the two tables, which would increase the number of duplicates. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.2 Given a scenario, execute

database tasks using scripting and programming languages.

Correct Answer: C

Correct Answer: AB