CompTIA DS0-001 Practice Test - Questions Answers, Page 6

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.Reference: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 must be considered to ensure data integrity during transmission is encryption. Encryption is a process that transforms data into an unreadable or scrambled form using an algorithm and a key. Encryption helps protect data integrity during transmission by preventing unauthorized access or modification of data by third parties, such as hackers, eavesdroppers, or interceptors. Encryption also helps verify the identity and authenticity of the source and destination of the data using digital signatures or certificates. The other options are either not related or not sufficient for this purpose. For example, bandwidth is the amount of data that can be transmitted over a network in a given time; redundancy is the duplication of data or components to provide backup or alternative sources in case of failure; masking is a technique that replaces sensitive data with fictitious but realistic data to protect its confidentiality or compliance.Reference:CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.

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

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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.Reference: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 should be used to analyze the database's structure is an ERD. An ERD, or Entity Relationship Diagram, is a graphical representation of the entities (tables), attributes (columns), and relationships (constraints) in a database. An ERD helps to visualize the structure and design of the database, as well as the dependencies and associations among the tables. An ERD can also help to evaluate the level of normalization of the database, which is a process that organizes data into tables and columns to reduce redundancy and improve consistency. By using an ERD, a database professional can consider denormalizing a database, which is a process that introduces some redundancy or duplication of data to improve performance or simplify queries. The other options are either different types of documents or not related to the database's structure. For example, an SOP, or Standard Operating Procedure, is a document that describes the steps and procedures for performing a specific task or operation; a data dictionary is a document that describes the metadata (information about data) of a database; a UML diagram is a graphical representation of a software system or its components using the Unified Modeling Language (UML).Reference:CompTIA DataSys+ Course Outline, Domain 2.0 Database Deployment, Objective 2.2 Given a scenario, create database objects using scripting and programming languages.

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.Reference: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 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.Reference:CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1 Given a scenario, identify common database types.

The option that sets the age requirement for data that should be recovered after a major disaster is RPO. RPO, or Recovery Point Objective, is a metric that defines the maximum amount of data that can be lost or acceptable data loss in the event of a disaster or disruption. RPO indicates how frequently the data should be backed up or replicated to minimize the risk of data loss. RPO also sets the age requirement for data that should be recovered after a major disaster, as it determines how far back in time the recovery process should go. For example, if the RPO is one hour, then the data should be backed up or replicated every hour, and the recovery process should restore the data to the state it was in one hour before the disaster. The other options are either different metrics or not related to data recovery at all. For example, MTBF, or Mean Time Between Failures, is a metric that measures the average time that a system or component operates without failure; RTO, or Recovery Time Objective, is a metric that defines the maximum amount of time that can be taken to restore a system or service after a disaster or disruption; MTTF, or Mean Time To Failure, is a metric that measures the average time that a system or component operates until it fails.Reference:CompTIA DataSys+ Course Outline, Domain 5.0 Business Continuity, Objective 5.3 Given a scenario, implement backup and restoration of data.

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.Reference:CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.1 Given a scenario, implement database infrastructure security.

The database structure that is a type of NoSQL database is key-value stores. Key-value stores are databases that store and manage data as pairs of keys and values. Keys are unique identifiers that locate data in the database; values are arbitrary data that can be any type or format. Key-value stores do not use any schema or structure to organize data, but rather use hash tables or indexes to enable fast and simple access to data based on keys. Key-value stores are suitable for storing large amounts of simple or unstructured data that do not require complex queries or relationships. The other options are either different types of databases or not related to database structures at all. For example, hierarchical databases are databases that store and manage data as nodes in a tree-like structure; cloud databases are databases that are hosted and accessed over the internet using cloud computing services; object-oriented databases are databases that store and manage data as objects that have attributes and methods.Reference:CompTIA DataSys+ Course Outline, Domain 1.0 Database Fundamentals, Objective 1.1 Given a scenario, identify common database types.