CompTIA CompTIA Certifications DS0-001 Questions & Answers

• Question 61:

  Which of the following statements contains an error?

  A. Select EmpId from employee where EmpId=90030

  B. Select EmpId where EmpId=90030 and DeptId=34

  C. Select* from employee where EmpId=90030

  D. Select EmpId from employee

  Correct Answer: B

  The statement that contains an error is option B. This statement is missing the FROM clause, which specifies the table or tables from which to retrieve data. The FROM clause is a mandatory clause in a SELECT statement, unless the

  statement uses a subquery or a set operator. The correct syntax for option B would be:

  SELECT EmpId FROM employee WHERE EmpId=90030 AND DeptId=34 Copy

  The other options are either correct or valid SQL statements. For example, option A selects the employee ID from the employee table where the employee ID is equal to 90030; option C selects all columns from the employee table where the

  employee ID is equal to 90030; option D selects the employee ID from the employee table without any filter condition. 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 62:

  A database administrator is creating a table, which will contain customer data, for an online business. Which of the following SQL syntaxes should the administrator use to create an object?

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: B

  The SQL syntax that the administrator should use to create an object is option B. This syntax uses the CREATE TABLE statement to define a new table named customer with four columns: customer_id, name, email, and phone. Each column has a data type and a constraint, such as NOT NULL or PRIMARY KEY. The other options either have syntax errors, use incorrect keywords, or do not specify the table name or columns correctly. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1 Given a scenario, identify and apply database structure types.

• Question 63:

  A DBA is reviewing the following logs to determine the current data backup plan for a primary data server:

  

  Which of the followingbestdescribes this backup plan?

  A. Monthly full, daily differential

  B. Daily differential

  C. Daily full

  D. Weekly full, daily incremental

  Correct Answer: D

  The backup plan that best describes the logs is weekly full, daily incremental. This means that a full backup of the entire database is performed once a week, and then only the changes made since the last backup are backed up every day. This can be inferred from the logs by looking at the size and duration of the backups. The full backups are larger and take longer than the incremental backups, and they occur every seven days. The other backup plans do not match the pattern of the logs. 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 64:

  Which of the following have data manipulation and procedural scripting power? (Choose two.)

  A. PQL

  B. PL/SQL

  C. Advanced

  D. SQL

  E. SQL

  F. T-SQL

  Correct Answer: BF

  The two options that have data manipulation and procedural scripting power are PL/SQL and T-SQL. PL/SQL, or Procedural Language/Structured Query Language, is an extension of SQL that adds procedural features to SQL for Oracle databases. PL/SQL allows users to create and execute stored procedures, functions, triggers, packages, etc., using variables, loops, conditions, exceptions, etc., in addition to SQL commands. PL/SQL helps improve the performance, functionality, modularity, and security of SQL queries and applications. T-SQL, or Transact-SQL, is an extension of SQL that adds procedural features to SQL for Microsoft SQL Server databases. T-SQL allows users to create and execute stored procedures, functions, triggers, etc., using variables, loops, conditions, exceptions, etc., in addition to SQL commands. T-SQL helps improve the performance, functionality, modularity, and security of SQL queries and applications. The other options are either not related or not having both data manipulation and procedural scripting power. For example, PQL, or Power Query Language, is a data analysis andtransformation language for Microsoft Power BI and Excel; Advanced SQL is a term that refers to the advanced features or techniques of SQL, such as subqueries, joins, aggregations, etc.; SQL, or Structured Query Language, is a standard language for manipulating and querying data in relational databases, but it does not have procedural features. 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 65:

  Which of the following cloud storage options provides users with endpoints to retrieve data via REST API?

  A. Network file

  B. Object

  C. Ephemeral

  D. iBIock

  Correct Answer: B

  The cloud storage option that provides users with endpoints to retrieve data via REST API is object. Object storage is a type of cloud storage that stores data as objects, which consist of data, metadata, and a unique identifier. Object storage does not use any hierarchy or structure to organize data, but rather uses flat namespaces that allow users to access data using the unique identifier. Object storage also provides users with endpoints to retrieve data via REST API (Representational State Transfer Application Programming Interface), which is a standard way of communicating with web services using HTTP methods (such as GET, POST, PUT, DELETE) and formats (such as JSON, XML). Object storage is suitable for storing large amounts of unstructured data that do not require frequent changes or complex queries. The other options are either different types of cloud storage or not related to cloud storage at all. For example, network file storage is a type of cloud storage that stores data as files in folders using protocols such as NFS (Network File System) or SMB (Server Message Block); ephemeral storage is a type of temporary storage that stores data only for the duration of a session or process; iBIock is not a valid acronym or type of cloud storage. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.1 Given a scenario, select an appropriate database deployment method.

• Question 66:

  A database administrator needs to provide access to data from two different tables to multiple group users in order to facilitate ongoing reporting. However, some columns in each table are restricted, and users should not be able to see the values in these columns.

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

  A. Create a stored procedure.

  B. Create a view.

  C. Create a csv export.

  D. Create a trigger.

  Correct Answer: B

  The best action for the administrator to take is to create a view. A view is a virtual table that shows a subset of data from one or more tables. The administrator can use a view to provide access to data from two different tables to multiple group users without exposing the restricted columns. The view can also simplify the queries and improve the performance of the reporting process. The other options are either not suitable for this scenario or do not address the requirement of hiding some columns from users. For example, creating a stored procedure would require additional coding and execution, creating a csv export would create a static file that may not reflect the latest data changes, and creating a trigger would perform an action in response to an event rather than provide access to data. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.2 Given a scenario, create database objects using scripting and programming languages.

• Question 67:

  A database administrator is concerned about transactions in case the system fails. Which of the following properties addresses this concern?

  A. Durability

  B. Isolation

  C. Atomicity

  D. Consistency

  Correct Answer: A

  The property that addresses this concern is durability. Durability is one of the four properties (ACID) that ensure reliable transactions in a database system. Durability means that once a transaction has been committed, its effects are permanent and will not be lost in case of system failure, power outage, crash, etc. Durability can be achieved by using techniques such as write-ahead logging, checkpoints, backup and recovery, etc. The other options are either not related or not specific to this concern. For example, isolation means that concurrent transactions do not interfere with each other and produce consistent results; atomicity means that a transaction is either executed as a whole or not at all; consistency means that a transaction preserves the validity and integrity of the data. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.3 Given a scenario, identify common database issues.

• Question 68:

  Which of the following services is responsible for assigning, managing, and reclaiming IP addresses on a TCP/IP-based network?

  A. DNS

  B. DHCP

  C. LDAP

  D. ISMTP

  Correct Answer: B

  The service that is responsible for assigning, managing, and reclaiming IP addresses on a TCP/IP-based network is DHCP. DHCP, or Dynamic Host Configuration Protocol, is a service that automatically assigns IP addresses and other network configuration parameters, such as subnet mask, default gateway, DNS server, etc., to computers or devices on a network. DHCP helps simplify the administration and management of IP addresses on a network, as well as avoid conflicts or errors caused by manual or duplicate assignments. DHCP also allows computers or devices to release or renew their IP addresses when they join or leave the network. The other options are either different services or not related to IP addresses at all. For example, DNS, or Domain Name System, is a service that translates domain names into IP addresses and vice versa; LDAP, or Lightweight Directory Access Protocol, is a service that provides access to directory information such as users, groups, or devices on a network; ISMTP is not a valid acronym or service. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.1 Given a scenario, select an appropriate database deployment method.

• Question 69:

  Which of the following should a company develop to ensure preparedness for a fire in a data center?

  A. Deployment plan

  B. Backup plan

  C. Data retention policy

  D. Disaster recovery plan

  Correct Answer: D

  The document that a company should develop to ensure preparedness for a fire in a data center is a disaster recovery plan. A disaster recovery plan is a document that outlines how an organization will continue its operations in the event of a disaster or disruption, such as fire, flood, earthquake, cyberattack, etc. A disaster recovery plan typically includes the followingelements: - The objectives and scope of the plan - The roles and responsibilities of the staff involved - The identification and assessment of the risks and impacts - The strategies and procedures for restoring the critical functions and data - The resources and tools required for the recovery process - The testing and maintenance schedule for the plan A disaster recovery plan helps an organization to minimize the damage and downtime caused by a disaster, as well as to resume normal operations as soon as possible. The other options are either different types of documents or not specific to fire preparedness. For example, a deployment plan is a document that describes how a system or software will be installed or launched; a backup plan is a document that specifies how data will be copied and stored for backup purposes; a data retention policy is a document that defines how long data should be kept and when it should be deleted or archived. References: CompTIA DataSys+ Course Outline, Domain 5.0 Business Continuity, Objective 5.4 Given a scenario, implement disaster recovery methods.

• Question 70:

  Which of the following is an advantage of creating indexes?

  A. To help with space allocation

  B. To provide quick and efficient access to data

  C. To reduce memory

  D. To update the query plan

  Correct Answer: B

  The advantage of creating indexes is to provide quick and efficient access to data. An index is a data structure that stores the values of one or more columns of a table in a sorted order, along with pointers to the corresponding rows in the table. An index helps to speed up queries thatsearch, filter, sort, or join data based on the indexed columns, as it reduces the number of disk accesses or scans required to locate the desired data. An index also helps to enforce uniqueness or referential integrity constraints on the indexed columns. The other options are either not true or not relevant for this purpose. For example, an index does not help with space allocation, as it consumes additional space in the database; an index does not reduce memory, as it may use memory for caching or buffering purposes; an index does not update the query plan, as it is an input or a factor for the query optimizer to generate the query plan. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.2 Given a scenario, execute database tasks using scripting and programming languages.