Views: Is a “dynamic view” (ordinary SQL view) one whose contents are computed on demand when the view is referenced, rather than stored physically?

Difficulty: Easy

Correct Answer: Applies — standard views are virtual and materialize at query time

Explanation:

Introduction / Context:The question distinguishes ordinary (virtual) views from materialized views. Understanding this affects performance expectations and refresh strategies.

Given Data / Assumptions:

  • Ordinary SQL views store only the definition (query), not the result set.
  • Materialized views (or snapshots) store results and need refresh.
  • Terminology “dynamic view” often refers to a virtual, on-demand view.

Concept / Approach:When you SELECT from a standard view, the DBMS expands it into the underlying query and executes it, producing results at that moment. No separate physical table holds the view’s data (unless specifically materialized).

Step-by-Step Solution:Interpret “contents materialize when referenced” as virtual evaluation.Recall the difference from materialized views.Conclude the statement is accurate for standard views.

Verification / Alternative check:Explain plans show the base tables accessed when selecting from a normal view.

Why Other Options Are Wrong:Not all views persist data; only materialized views do. Join usage does not change virtual vs. materialized nature.

Common Pitfalls:Expecting performance like a precomputed table; if you need persisted results, use materialized views and manage refresh.

Final Answer:Applies — standard views are virtual and materialize at query time

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