Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
Views are pervasive in database development, used for security, abstraction, and reuse. This question asks whether a view can be described as a virtual table built from other tables or views. It checks your grasp of the conceptual model rather than performance specifics.
Given Data / Assumptions:
Concept / Approach:
A view presents the result of a stored query as if it were a table. The engine evaluates the view definition (often by query rewrite) against base tables or even other views. Thus, describing a view as a “virtual table constructed from other tables or views” is accurate. Whether it is updatable or materialized does not change that fundamental definition; those are properties or implementations layered on top.
Step-by-Step Solution:
Verification / Alternative check:
Querying a view with SELECT * FROM v behaves like querying a table; dropping referenced tables invalidates the view, showing its dependence on other objects.
Why Other Options Are Wrong:
Common Pitfalls:
Believing views always store data; conflating materialized views with standard views; assuming views must be updatable.
Final Answer:
Correct
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