Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
Attributes are the named data elements that describe an entity’s characteristics (e.g., Customer.Name, OrderDate, Salary). Correctly modeling attributes is essential for normalization, constraints, and data quality rules.
Given Data / Assumptions:
Concept / Approach:
Attributes define what you store about each instance. They can be simple, composite, multi-valued (conceptually), or derived. During relational transformation, attributes become columns with data types, nullability, and constraints.
Step-by-Step Solution:
Pick an entity (e.g., Employee). List attributes (EmpID, Name, HireDate, Salary). Classify attributes: identifier vs. descriptive vs. derived. Map to table columns and specify types/constraints.
Verification / Alternative check:
Check whether each attribute is atomic and relevant to the entity; if not, consider new entities or normalization (e.g., split Address).
Why Other Options Are Wrong:
“Incorrect” contradicts the standard definition; restricting to weak entities or numeric data is unfounded.
Common Pitfalls:
Embedding multiple facts in one attribute; ignoring derived/calculated values vs. stored values; failing to enforce domain constraints.
Final Answer:
Correct
Discussion & Comments