CompTIA DS0-001 - Questions & Answers

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.

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.

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 purpose of a snapshot is to create an image of a database. A snapshot is a copy of the state and content of a database at a specific point in time. A snapshot can be used for various purposes, such as backup and recovery, testing and development, reporting and analysis, etc. A snapshot can be created using various techniques, such as full copy, incremental copy, differential copy, etc. A snapshot can also be created using various tools or commands provided by the database system or software. The other options are either incorrect or irrelevant for this question. For example, dynamic data replication is a process that copies and synchronizes data from one database server (the source) to one or more
database servers (the target) in real time; a synonym is an alias or an alternative name for an object in a database; C is an incomplete option.
References:
CompTIA DataSys+ Course Outline, Domain 5.0
Business Continuity, Objective 5.2 Given a scenario, implement backup and restoration of database management systems.

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.

A reason to create a stored procedure is to improve performance. A stored procedure is a set of SQL statements or commands that are stored and compiled in the database server, and can be executed by name or by a trigger. A stored procedure can improve performance by reducing the network traffic between the client and the server, as only the name or the parameters of the stored procedure need to be sent, rather than the entire SQL code. A stored procedure can also improve performance by reusing the same execution plan, as the stored procedure is compiled only once and cached in the server memory.
The other options are either not true or not relevant for this purpose. For example, a stored procedure does not necessarily minimize storage space, as it still occupies space in the database server; a stored
procedure does not bypass case sensitivity requirements, as it still follows the rules of the database system; a stored procedure does not give control of the query logic to the user, as it is defined and
maintained by the database administrator or developer.
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 characteristic of all non-relational databases is unstructured data. Unstructured data is data that does not have a predefined or fixed format, schema, or structure. Unstructured data can include various types of data, such as text, images, audio, video, etc. Non-relational databases, also known as NoSQL databases, are databases that store and manage unstructured data using different models, such as key-value, document, graph, columnar, etc. Non-relational databases are suitable for handling large volumes, variety, and velocity of data that do not fit well in the relational model. The other options are either characteristics of relational databases or not related to database types at all. For example, columns with the same data type, logical record groupings, and tabular schema are characteristics of relational databases, which are databases that store and manage structured data using tables, rows, columns, and constraints.
References:
CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1
Given a scenario, identify common database types.

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 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.