DS0-001 Dumps with Practice Exam Questions Answers

The ORM snippet that would return the ID, state, and country of all customers with the newest customers appearing first is option C. This snippet uses the select method to specify the columns to be returned, the order method to sort the results by ID in descending order, and the all method to fetch all the records. The other options either have syntax errors, use incorrect methods, or do not sort the results correctly. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.2 Given a scenario, execute database tasks using scripting and programming languages.

The index that stores records in a tabular format is columnstore. A columnstore index is a type of index that stores and compresses data by columns rather than by rows. A columnstore index can improve the performance and efficiency of queries that perform aggregations, calculations, or analysis on large amounts of data, such as data warehouse or business intelligence applications. A columnstore index can also reduce the storage space required for data by applying various compression techniques, such as dictionary encoding, run-length encoding, bit packing, etc. The other options are either different types of indexes or not related to indexes at all. For example, a non-clustered index is a type of index that stores the values of one or more columns in a sorted order along with pointers to the corresponding rows in the table; a unique index is a type of index that enforces uniqueness on one or more columns in a table; a secondary index is an alternative term for a non-clustered index. References: CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.1 Given a scenario, perform common database maintenance tasks.

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.

The best suited database engine for this task is MongoDB. MongoDB is a type of non-relational database that stores data as documents in JSON-like format. MongoDB allows administrators to perform quick and simple queries on unstructured data, such as text, images, videos, or social media posts, without requiring a predefined schema or complex joins. MongoDB also supports cloud-based deployment, scalability, and high availability. The other options are either relational databases that require a fixed schema and structure for data, or specialized databases that are designed for specific purposes, such as graph databases for storing and analyzing network data. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1 Given a scenario, identify and apply database structure types.

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.