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The WITH CHECK OPTION clause ensures that any inserts or updates to the view comply with the criteria defined in the view’s SELECT statement. If a DML operation would result in a row that doesn’t meet the view’s criteria, it will be rejected.Example: Explanation: This ensures that any updates made through the high_salary_employees view must…

Unlike regular views, materialized views store the result of a query physically on disk. This allows for faster access to data since it does not need to be re-computed every time it is queried. Creating a Materialized View: Explanation: This creates a materialized view named mv_employee_salaries, which calculates and stores the average salary for each…

To remove a view from the database, you use: Example: Explanation: This command deletes the employee_view from the database, meaning it can no longer be queried or used.

To change the definition of an existing view, you can use the CREATE OR REPLACE VIEW statement: Example Explanation: This updates the employee_view to include the department_id column and maintains the same salary filter.

Some views can be updated directly if they meet certain criteria (e.g., they reference a single table without aggregate functions).Syntax: Example: Explanation: This updates the salary of the employee with employee_id 1, increasing it by 10%. The update reflects in the underlying employees table.

You can query a view just like you would a regular table: Explanation: This retrieves all rows from the employee_view, showing only employees who meet the salary condition set during the view’s creation.

Syntax Example Explanation: This creates a view called employee_view that includes only employees with a salary greater than 50,000. The view presents selected columns (employee_id, first_name, last_name, salary) from the employees table.