CompTIA Updated DA0-001 Exam Questions and Answers by marlo

When designing a database schema that represents a central entity with multiple levels of related subcategories, it's crucial to choose a structure that efficiently models these relationships.

Option A:Relational

Rationale: A relational database organizes data into tables with rows and columns, using keys to establish relationships between tables. While flexible, the relational model doesn't inherently represent hierarchical relationships, making it less ideal for schemas requiring parent-child data representation.

Option B:Hierarchical

Rationale: The hierarchical database model structures data in a tree-like format, with a single root (central group) and multiple levels of nested subcategories (parent-child relationships). This model is well-suited for scenarios where data is naturally hierarchical, such as organizational charts or file systems.

The mean (average) is the most sensitive measure when it comes to outliers. If a dataset contains extreme values (either very high or very low), they disproportionately affect the mean, making it a less robust measure of central tendency​.

Explanation

Cross-site Scripting (XSS) is a security vulnerability usually found in websites and/or web applications that accept user input.

XSS is a client-side vulnerability that targets other application users, while SQL injection is a server-side vulnerability that targets the application's database. How do I prevent XSS in PHP? Filter your inputs with a whitelist of allowed characters and use type hints or type casting.