DS0-001 CompTIA DataSys+ Certification Exam Free Practice Exam Questions (2025 Updated)

The index that the developer should use to prevent duplicate values from being inserted is unique. A unique index is a type of index that enforces the uniqueness of the values in one or more columns of a table. A unique index ensures that no two rows in the table have the same value or combination of values in the indexed columns. A unique index helps to maintain data integrity and avoid data duplication or inconsistency. The other options are either not related or not effective for this purpose. For example, a single column index is a type of index that involves only one column of a table, but it does not prevent duplicate values unless it is also unique; an implicit index is a type of index that is automatically created by the database system when a constraint or a primary key is defined on a column or columns of a table, but it does not prevent duplicate values unless it is also unique; a composite index is a type of index that involves two or more columns of a table, but it does not prevent duplicate values unless it is also unique. 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 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.

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 tool for the database administrator to document and explain the relationships between data in an organization’s database is a UML editor. A UML editor is a software application that allows users to create, edit, and visualize diagrams using the Unified Modeling Language (UML). UML is a standard language for modeling software systems and their components, such as classes, objects, relationships, behaviors, etc. UML can also be used to document and explain the relationships between data in an organization’s database by creating entity relationship diagrams (ERDs), which are graphical representations of the entities (tables), attributes (columns), and relationships (constraints) in a database. A UML editor can help the administrator to document and explain the relationships between data by providing features such as drag-and-drop, templates, symbols, validation, etc. The other options are either not suitable or not optimal for this task. For example, a text editor is a software application that allows users to create and edit plain text files; a word processor is a software application that allows users to create and edit text documents; an SQL query is a statement that performs an operation on a database using Structured Query Language (SQL). References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.2 Given a scenario, create database objects using scripting and programming languages.

The computer service that associates IP network addresses with text-based names in order to facilitate identification and connectivity is IDNS. IDNS, or Internet Domain Name System (DNS), is a service that translates domain names into IP addresses and vice versa. Domain names are human-readable names that identify websites or devices on the internet, such as www.comptia.org or www.google.com. IP addresses are numerical identifiers that locate websites or devices on the internet, such as 104.18.26.46 or 142.250.72.238. IDNS helps users to access websites or devices using domain names instead of IP addresses, which are easier to remember and type. IDNS also helps administrators to manage websites or devices using domain names instead of IP addresses, which are more flexible and scalable. The other options are either different computer services or not related to IP network addresses or text-based names at all. For example, LDAP, or Lightweight Directory Access Protocol, is a service that provides access to directory information such as users, groups, or devices on a network; NTP, or Network Time Protocol, is a service that synchronizes the clocks of computers or devices on a network; DHCP, or Dynamic Host Configuration Protocol, is a service that assigns IP addresses and other network configuration parameters to computers or devices on a network.  References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.1 Given a scenario, select an appropriate database deployment method.

The option that is part of logical database infrastructure security is perimeter network. Perimeter network, also known as DMZ (Demilitarized Zone), is a network segment that lies between an internal network and an external network, such as the internet. Perimeter network provides an additional layer of security for the internal network by isolating and protecting the servers or services that are exposed to the external network, such as web servers, email servers, database servers, etc. Perimeter network also helps prevent unauthorized access or attacks from the external network to the internal network by using firewalls, routers, proxies, etc. The other options are either part of physical database infrastructure security or not related to database infrastructure security at all. For example, surveillance is a method of monitoring and recording physical activities or events in a location or resource; biometric access is a device that uses biological characteristics to control access to a physical location or resource; cooling system is a device or system that regulates the temperature and humidity of a location or resource. References: CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.1 Given a scenario, implement database infrastructure security.

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.

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.

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.

The option that best describes a collection of data that shares the same properties or attributes is entity set. An entity set is a term used in the entity-relationship (ER) model, which is a conceptual model for designing and representing databases. An entity set is a collection of entities that have the same type or characteristics, such as students, courses, products, etc. An entity is an object or thing that can be identified and distinguished from others, such as a specific student, course, product, etc. An entity set can have one or more attributes that describe the properties or features of the entities, such as name, age, price, etc. An entity set can also have one or more relationships with other entity sets that define how the entities are associated or connected, such as enrolled, taught by, purchased by, etc. The other options are either different terms or not related to the ER model at all. For example, relation set is a term used in the relational model, which is a logical model for implementing and manipulating databases; ER model is a term used to refer to the entity-relationship model itself; tuples are rows or records in a table or relation. References: CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1 Given a scenario, identify common database types.

The command that the database administrator should use for this task is SELECT. The SELECT command is a SQL statement that retrieves data from one or more tables or views in a database. The SELECT command can also use various clauses or options to filter, group, sort, or aggregate data according to specific criteria or conditions. By using the SELECT command, the database administrator can obtain information about the performance of users in the sales department, such as their sales volume, revenue, commission, etc. The other options are either not related or not suitable for this task. For example, DROP is a SQL command that deletes an existing table or object from a database; UPDATE is a SQL command that modifies existing data in one or more rows of a table; DELETE is a SQL command that removes existing data from one or more rows of 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.

The document that the administrator should create to illustrate the interaction between tables is an entity relationship diagram. An entity relationship diagram (ERD) is a graphical representation of the entities (tables), attributes (columns), and relationships (constraints) in a database. An ERD helps the administrator to visualize the structure and design of the database, as well as the dependencies and associations among the tables. The other options are either different types of documents or not related to the interaction between tables. For example, a troubleshooting guide is a document that provides instructions on how to solve common problems or errors in a database; a data dictionary is a document that describes the metadata (information about data) of a database; a database reference manual is a document that provides information on how to use or operate a database. References: CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.2 Given a scenario, create database objects using scripting and programming languages.

The factor that the administrator should measure to analyze a database server’s disk throughput is IOPS. IOPS, or Input/Output Operations Per Second, is a metric that measures the number of read and write operations that a disk can perform in one second. IOPS indicates the performance or speed of a disk and how well it can handle multiple requests or transactions. Higher IOPS means higher disk throughput and lower latency. IOPS can be affected by various factors, such as disk type, size, speed, cache, RAID level, etc. The other options are either not related or not sufficient for this purpose. For example, RPfvl is not a valid acronym or metric; latency is the time delay between a request and a response; reads are the number of read operations performed by a disk. References: CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.2 Given a scenario, monitor database performance.

The most likely way to prevent this issue is to use service accounts. Service accounts are special accounts that are used by applications or services to perform tasks or run jobs on behalf of users. Service accounts have limited permissions and access rights that are tailored to their specific functions. By using service accounts, the DBA can ensure that scheduled jobs can run independently of individual user accounts, and avoid failures due to account removal or changes. The other options are either not related or not effective for this issue. For example, load balancing is a technique that distributes the workload across multiple servers or resources to improve performance and availability; business continuity plan is a plan that outlines how an organization will continue its operations in the event of a disaster or disruption; assigning a data steward is a process that designates a person who is responsible for ensuring the quality and governance of data. References: CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.3 Given a scenario, migrate data between databases.

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.

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 script that would set the database recovery model for sys.database is option A. This script uses the ALTER DATABASE statement to modify the recovery model of the sys.database to full with no wait. The other options either have syntax errors, use incorrect keywords, or do not specify the recovery model correctly. References: CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.1 Given a scenario, perform common database maintenance tasks.

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.

The option that is most likely to prevent tampering with server hardware that houses data is biometric locks. Biometric locks are devices that use biological characteristics, such as fingerprints, facial recognition, iris scan, etc., to control access to a physical location or resource. Biometric locks help prevent tampering with server hardware that houses data by restricting unauthorized entry or theft of the hardware by intruders or attackers. Biometric locks also provide higher security and convenience than other types of locks, such as keys or passwords, which can be lost, stolen, or forgotten. The other options are either not related or not effective for this purpose. For example, a strong password policy is a set of rules or standards for creating and managing passwords for user accounts or systems; a network firewall is a device or software that controls the incoming and outgoing traffic on a network based on a set of rules or policies; surveillance cameras are devices that capture and record video footage of a physical location or resource. References: CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.