CompTIA DS0-001 Practice Test - Questions Answers, Page 5

The option that the administrator should implement to ensure high availability of the database is replication. Replication is a process that copies and synchronizes data from one database server (the primary or source) to one or more database servers (the secondary or target). Replication helps ensure high availability of the database by providing redundancy, fault tolerance, and load balancing. If the primary server fails, the secondary server can take over and continue to serve the data without interruption or data loss. The other options are either not related or not suitable for this purpose. For example, ETL is a process that extracts, transforms, and loads data from one source to another for analysis or reporting purposes; database dumping is a process that exports the entire content of a database to a file for backup or migration purposes; backup and restore is a process that copies and recovers data from a backup device or media in case of a disaster or corruption.Reference:CompTIA DataSys+ Course Outline, Domain 5.0 Business Continuity, Objective 5.3 Given a scenario, implement replication of database management systems.

The first thing that the database administrator should examine to troubleshoot the issue is the event log. The event log is a file that records the events and activities that occur on a system, such as database backups, errors, warnings, or failures. By examining the event log, the administrator can identify the cause and time of the backup failure, and also check for any other issues or anomalies that may affect the backup process or the backup quality. The other options are either not relevant or not the first priority for this task. For example, CPU usage, disk space, and OS performance may affect the performance or availability of the system, but not necessarily cause the backup failure; moreover, these factors can be checked after reviewing the event log for more information.Reference:CompTIA DataSys+ Course Outline, Domain 5.0 Business Continuity, Objective 5.2 Given a scenario, implement backup and restoration of database management systems.

The best option for the database administrator to use to update an organization's ERD is a UML tool. A UML tool 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 create entity relationship diagrams (ERDs), which are graphical representations of the entities (tables), attributes (columns), and relationships (constraints) in a database. A UML tool can help the administrator to update an organization's ERD 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 word processor is a software application that allows users to create and edit text documents; a spreadsheet is a software application that allows users to organize and manipulate data in rows and columns; an HTML editor is a software application that allows users to create and edit web pages using HyperText Markup Language (HTML).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 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).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 practice that best describes this request is access control. Access control is a process that regulates who can access what data in a system based on predefined rules or policies. Access control helps protect data from unauthorized or inappropriate access or modification by granting or denying permissions or privileges to users or groups based on their roles or identities. By applying access control, the database administrator can assign a user the ability to view a data set without allowing them to change or delete it. The other options are either different practices or not related to this request. For example, security audit is a process that evaluates the security level of a system by identifying vulnerabilities or risks; database audit is a process that monitors and records the activities or events that occur on a database; password policy implementation is a process that defines and enforces rules or standards for creating and managing passwords.Reference:CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.

The firewall type that allows an administrator to control traffic and make decisions based on factors such as connection information and data flow communications is stateful. A stateful firewall is a type of firewall that tracks the state of each connection and packet that passes through it, and applies rules or policies based on the context and content of the traffic. A stateful firewall can control traffic and make decisions based on factors such as source and destination IP addresses, ports, protocols, session status, application layer data, etc. The other options are either different types of firewalls or not related to firewalls at all. For example, a circuit-level firewall is a type of firewall that monitors and validates the establishment of TCP or UDP connections; a proxy firewall is a type of firewall that acts as an intermediary between the source and destination of the traffic; a packet firewall is a type of firewall that filters packets based on their header information.Reference:CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.

The command that the database administrator should use for this task is CREATE USER. The CREATE USER command is a SQL statement that creates a new user account in a database and assigns it a username and a password. The CREATE USER command also allows the database administrator to specify other options or attributes for the user account, such as default tablespace, quota, profile, role, etc. The CREATE USER command is the first step to enable a user to authenticate to a database. The other options are either invalid or not suitable for this task. For example, INSERT USER is not a valid SQL command; ALLOW USER is not a SQL command, but a keyword used in some database systems to grant permissions to users; ALTER USER is a SQL command that modifies an existing user account, but does not create a new one.Reference:CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.

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.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 two factors that the database administrator should monitor to gauge server health are CPU usage and memory usage. CPU usage is the percentage of time that the processor (CPU) of the server is busy executing instructions or processes. CPU usage indicates how much workload the server can handle and how fast it can process requests. High CPU usage may affect the performance or availability of the server and cause delays or errors. Memory usage is the amount of physical memory (RAM) or virtual memory (swap space) that the server uses to store data or run applications. Memory usage indicates how much space the server has to store temporary or intermediate data or results. High memory usage may affect the performance or availability of the server and cause swapping or paging. The other options are either not relevant or not direct indicators of server health. For example, transaction logs are files that record the changes made by transactions on the database; network sniffer is a tool that captures and analyzes network traffic; domain controllers are servers that manage user authentication and authorization in a network; firewall traffic is the amount of data that passes through a firewall device or software.Reference:CompTIA DataSys+ Course Outline, Domain 3.0 Database Management and Maintenance, Objective 3.2 Given a scenario, monitor database performance.