DS0-001 Exam Dumps - CompTIA DataSys+ Certification Exam

The correct answer is C. An exact match is not possible in a SELECT statement. CompTIA DataSys+ documentation explains that wildcards are used in SQL primarily within the WHERE clause of a SELECT statement to enable pattern matching rather than exact value matching. Wildcards such as % and _ are commonly used with the LIKE operator to search for partial strings or variable patterns in character-based data.

In practical database usage, wildcards allow analysts and administrators to retrieve records when the full or exact value is unknown or unnecessary. For example, searching for all patient records with last names starting with “Mac%” or all email addresses ending in “@example.com” requires pattern-based matching. In these cases, an exact match is explicitly not required, which is the core purpose of wildcards in SQL queries.

Option A and D incorrectly reference the CREATE statement. Wildcards are not relevant to CREATE statements, which are used for defining database objects such as tables, indexes, or views. These statements require explicit definitions and do not support wildcard-based matching logic. Option B is also incorrect because a SELECT statement does not always require an exact match; this is precisely why wildcards exist and are heavily used in querying operations.

CompTIA DataSys+ emphasizes that understanding query flexibility is essential for data retrieval and reporting. Wildcards enhance query usability and efficiency by allowing broader result sets without complex logic or multiple conditions. They are particularly valuable in analytical, reporting, and troubleshooting scenarios where partial data exploration is required.

Therefore, the best description of the function of a wildcard in the WHERE clause is that it allows queries where an exact match is not required, making option C the correct and fully aligned answer according to CompTIA DataSys+ principles.

The option that is used to hide data in a database so the data can only be read by a user who has a key is data encryption. Data encryption is a process that transforms data into an unreadable or scrambled form using an algorithm and a key. Data encryption helps protect data from unauthorized access or modification by third parties, such as hackers, eavesdroppers, or interceptors. Data encryption also helps verify the identity and authenticity of the source and destination of the data using digital signatures or certificates. Data encryption can be applied to data at rest (stored in a database) or data in transit (transmitted over a network). To read encrypted data, a user needs to have the corresponding key to decrypt or restore the data to its original form. The other options are either different concepts or not related to hiding data at all. For example, data security is a broad term that encompasses various methods and techniques to protect data from threats or risks; data masking is a technique that replaces sensitive data with fictitious but realistic data to protect its confidentiality or compliance; data protection is a term that refers to the legal or ethical obligations to safeguard personal or sensitive data from misuse or harm. References: CompTIA DataSys+ Course Outline, Domain 4.0 Data and Database Security, Objective 4.2 Given a scenario, implement security controls for databases.

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. References: CompTIA DataSys+ Course Outline, Domain 5.0 Business Continuity, Objective 5.2 Given a scenario, implement backup and restoration of database management systems.