Difficulty: Easy
Correct Answer: All of the above are uses for SQL views
Explanation:
Introduction / Context:Views are powerful for security and abstraction. They can filter rows, project specific columns, and encapsulate complex joins and calculations behind a simple name.
Given Data / Assumptions:
Concept / Approach:Because a view is defined by an arbitrary SELECT, it can include or exclude columns, include conditions to restrict rows, and combine multiple tables. Thus, all three use cases apply.
Step-by-Step Solution:
Assess each offered use: column projection, row filtering, complexity hiding.Recognize all are achievable via the view’s SELECT definition.Therefore choose the combined option.Verification / Alternative check:Create sample views: one selecting limited columns, one with WHERE department_id = 10, and one wrapping a complex join. All are valid and useful.
Why Other Options Are Wrong:Each individual option is too narrow; views support more than a single purpose.
Common Pitfalls:Relying on views alone for security: combine with proper privileges and, when needed, row-level security policies for robust protection.
Final Answer:All of the above are uses for SQL views
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