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The WITH READ ONLY clause prevents any DML operations (INSERT, UPDATE, DELETE) on the view. This is useful for views intended solely for data retrieval. Example Explanation: This view can be queried but cannot be modified. It provides a safeguard against accidental data changes, ensuring data integrity.

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.