Question
CREATE OR REPLACE VIEW high _ salary _ employees AS
SELECT employee _ id, salary FROM employees WHERE salary > 50000; Which statement about the view high _ salary _ employees is true?Solution
A SQL view is a virtual table that reflects the results of a query in real-time. 1. Dynamic Nature: A view does not store data itself but retrieves data dynamically from the underlying table when queried. 2. Purpose: The high _ salary _ employees view reflects any updates made to the employees table that meet the specified condition (salary > 50000). 3. Real-Time Updates: Changes to the employees table are automatically visible in the view without needing to recreate it. This behavior makes views ideal for abstraction and encapsulation in SQL. Why Other Options Are Incorrect: • A) The view stores a copy of the data in the database: A view is virtual and does not store data physically. • B) The view must be recreated if the employees table is updated: The view dynamically reflects updates to the employees table. • D) The view can be used to perform DML operations directly on employees: Views are read-only unless explicitly defined as updatable. • E) The view is static and cannot be updated: Views are dynamic and reflect real-time data.
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