CompTIA DS0-001 Online Practice Questions and Exam Preparation

CompTIA DS0-001 Online Questions & Answers

• Question 41:

  Which of the following commands is part of DDL?

  A. UPDATE
  B. GRANT
  C. CREATE
  D. INSERT
  C. CREATE

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  Explanation/Reference:

  The command that is part of DDL is CREATE. CREATE is a SQL command that belongs to the category of DDL, or Data Definition Language. DDL is a subset of SQL commands that are used to define or modify the structure or schema of a

  database, such as tables, columns, constraints, indexes, views, etc. CREATE is a DDL command that is used to create a new object in a database, such as a table, column, constraint, index, view, etc. For example, the following statement

  uses the CREATE command to create a new table called employee with four columns:

  CREATE TABLE employee (

  emp_id INT PRIMARY KEY,

  emp_name VARCHAR(50) NOT NULL,

  emp_dept VARCHAR(20),

  emp_salary DECIMAL(10,2)

  );

  Copy

  The other options are either part of different categories of SQL commands or not SQL commands at all. For example, UPDATE is a SQL command that belongs to the category of DML, or Data Manipulation Language. DML is a subset of SQL

  commands that are used to manipulate or modify the data or content of a database, such as inserting, updating, deleting, or selecting data. GRANT is a SQL command that belongs to the category of DCL, or Data Control Language. DCL is a

  subset of SQL commands that are used to control or manage the access or permissions of users or roles on a database, such as granting or revoking privileges or roles. INSERT is a SQL command that belongs to the category of DML, or

  Data Manipulation Language. INSERT is a DML command that is used to insert new data into a table. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.2 Given a scenario, execute database

  tasks using scripting and programming languages.

• Question 42:

  A database administrator manages a database server that is running low on disk space. A lot of backup files are stored on the server's disks.

  Which of the following is thebestaction for the administrator to take?

  A. Move all the backup files to external disks.
  B. Delete all the backup files containing data that is rated as classified.
  C. Delete all the backup files that are not required by the backup retention policy.
  D. Delete all the backup files except for the most recent one.
  C. Delete all the backup files that are not required by the backup retention policy.

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  Explanation/Reference:

  The best action for the administrator to take is to delete all the backup files that are not required by the backup retention policy. This will free up disk space on the server and also comply with the best practices for data backup and recovery. The backup retention policy defines how long the backup files should be kept and when they should be deleted or archived. The other options are either risky, inefficient, or impractical. For example, moving all the backup files to external disks would require additional hardware and time, deleting all the backup files containing data that is rated as classified would compromise data security and compliance, and deleting all the backup files except for the most recent one would limit the recovery options in case of a disaster. References: CompTIA DataSys+ Course Outline, Domain 5.0 Business Continuity, Objective 5.2 Given a scenario, implement backup and restoration of database management systems.

• Question 43:

  Which of the following constraints is used to enforce referential integrity?

  A. Surrogate key
  B. Foreign key
  C. Unique key
  D. Primary key
  B. Foreign key

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  Explanation/Reference:

  The constraint that is used to enforce referential integrity is foreign key. A foreign key is a column or a set of columns in a table that references the primary key of another table. A primary key is a column or a set of columns in a table that uniquely identifies each row in the table. Referential integrity is a rule that ensures that the values in the foreign key column match the values in the primary key column of the referenced table. Referential integrity helps maintain the consistency and accuracy of the data across related tables. The other options are either different types of constraints or not related to referential integrity at all. For example, a surrogate key is a column that is artificially generated to serve as a primary key, such as an auto-increment number or a GUID (Globally Unique Identifier); a unique key is a column or a set of columns in a table that uniquely identifies each row in the table, but it can have null valuesunlike a primary key; there is no such constraint as TID. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.2 Given a scenario, execute database tasks using scripting and programming languages.

• Question 44:

  Which of the following is the correct order of the steps in the database deployment process?

  A. 1. Connect 2. Install 3. Configure 4. Confirm prerequisites 5. Validate 6. Test 7. Release
  B. 1. Configure 2. Install 3. Connect 4. Test 5. Confirm prerequisites 6. Validate 7. Release
  C. 1. Confirm prerequisites 2. Install 3. Configure 4. Connect 5. Test 6. Validate 7. Release
  D. 1. Install 2. Configure 3. Confirm prerequisites 4. Connect 5. Test 6. Validate 7. Release
  C. 1. Confirm prerequisites 2. Install 3. Configure 4. Connect 5. Test 6. Validate 7. Release

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  Explanation/Reference:

  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.

• Question 45:

  Which of the following describes a scenario in which a database administrator would use a relational database rather than a non-relational database?

  A. An organization wants to maintain consistency among the data in the database.
  B. An organization requires data encryption.
  C. An organization wants to process complex data sets.
  D. An organization wants to store a large number of videos, photos, and documents.
  A. An organization wants to maintain consistency among the data in the database.

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  Explanation/Reference:

  A scenario in which a database administrator would use a relational database rather than a non-relational database is when an organization wants to maintain consistency among the data in the database. A relational database is a type of database that organizes data into tables with predefined columns and rows, and enforces rules and constraints to ensure data integrity and accuracy. A relational database also supports transactions, which are sets of operations that must be executed as a whole or not at all, to prevent data corruption or inconsistency. The other options are either not exclusive to relational databases or not relevant to the choice of database type. For example, data encryption can be applied to both relational and non-relational databases, processing complex data sets may require specialized tools or techniques that arenot dependent on the database type, and storing a large number of videos, photos, and documents may be better suited for a non-relational database that can handle unstructured or semi-structured data. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1 Given a scenario, identify and apply database structure types.

• Question 46:

  Following a security breach, a database administrator needs to ensure users cannot change data unless a request is approved by the management team. Which of the following principles addresses this issue?

  A. Open access
  B. Least resistance
  C. Elevated privilege
  D. Least privilege
  D. Least privilege

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  Explanation/Reference:

  The principle that addresses this issue is least privilege. Least privilege is a security principle that states that users should only have the minimum level of access or permissions required to perform their tasks or roles. By applying this principle, the administrator can ensure that users cannot change data unless they have been authorized by the management team through a request approval process. This prevents unauthorized or accidental modifications of data that may compromise its integrity or security. The other options are either opposite or unrelated to this principle. For example, open access means that users have unrestricted access to data; least resistance means that users have the easiest or most convenient access to data; elevated privilege means that users have higher or more permissions than they need. References: CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.1 Given a scenario, apply security principles and best practices for databases.

• Question 47:

  A database administrator is conducting a stress test and providing feedback to a team that is developing an application that uses the Entity Framework. Which of the following explains the approach the administrator should use when conducting the stress test?

  A. Capture business logic, check the performance of codes, and report findings.
  B. Check the clustered and non-clustered indexes, and report findings.
  C. Review application tables and columns, and report findings.
  D. Write queries directly into the database and report findings.
  A. Capture business logic, check the performance of codes, and report findings.

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  Explanation/Reference:

  The approach that the administrator should use when conducting the stress test is to capture business logic, check the performance of codes, and report findings. This will help the administrator to evaluate how well the application handles high volumes of data and transactions, identify any bottlenecks or errors in the code, and provide feedback to the development team on how to improve the application's efficiency and reliability. The other options are either too narrow or too broad in scope, and do not address the specific needs of an application that uses the Entity Framework. References: CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.3 Given a scenario, monitor database performance and security.

• Question 48:

  Which of the following indexes stores records in a tabular format?

  A. Columnstore
  B. Non-clustered
  C. Unique
  D. Secondary
  A. Columnstore

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  Explanation/Reference:

  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.

• Question 49:

  A programmer wants to configure a database to only allow read or write access when requests are coming from specific IP addresses. Which of the following can be used to configure IP addresses to allow access to the database?

  A. Static IP address
  B. Firewall
  C. Dynamic IP address
  D. IDNS
  B. Firewall

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  Explanation/Reference:

  The best option to configure IP addresses to allow access to the database is a firewall. A firewall is a network device or software that controls the incoming and outgoing traffic based on a set of rules or policies. A firewall can be used to filter the traffic by IP addresses, ports, protocols, or other criteria, and allow or deny access to the database accordingly. The other options are either not relevant or not sufficient for this task. For example, a static IP address is an IP address that does not change over time, but it does not determine the access to the database; a dynamic IP address is an IP address that changes periodically, but it does not control the traffic to the database; an IDNS is an Internet Domain Name System, which translates domain names into IP addresses, but it does not regulate the access to the database. References: CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.

• Question 50:

  Which of the following is thebestway to migrate a large data load from one table to another, considering total time and blocking?

  A. Split the load size into many transactions.
  B. Split the load size in half and run simultaneously.
  C. Batch into small loads and run in parallel.
  D. Batch large loads into one transaction.
  C. Batch into small loads and run in parallel.

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  Explanation/Reference:

  The best way to migrate a large data load from one table to another, considering total time and blocking, is to batch into small loads and run in parallel. This means that the large data load is divided into smaller chunks that can be processed simultaneously by multiple threads or processes. This reduces the total time required for the migration and also minimizes the blocking of other operations on the tables involved. The other options are either less efficient or more prone to blocking. For example, splitting the load size into many transactions may increase the overhead and latency of each transaction; splitting the load size in half and running simultaneously may still cause blocking or contention; batching large loads into one transaction may take longer and lock the tables for longer periods. References: CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.3 Given a scenario, migrate data between databases.