When a VIEW is created in SQL, users mayinsert or updatedata through that view. However, if a row is inserted or updated in such a way that itviolates the conditionof the VIEW’s WHERE clause, it can lead to inconsistencies.
Topreventsuch unwanted modifications,SQL provides the WITH CHECK OPTION clause.
How WITH CHECK OPTION Works:
Ensures thatany new data (INSERT/UPDATE) still fits within the defined constraints of the VIEW.
If a user tries to insert or update a row that would not appear in the VIEW,the operation isrejected.
Example:
sql
CREATE VIEW HighSalaryEmployees AS
SELECT * FROM Employees WHERE Salary > 50000
WITH CHECK OPTION;
Now, if someone attempts:
sql
INSERT INTO HighSalaryEmployees (ID, Name, Salary)
VALUES (101, 'Alice', 30000);
Thisfailsbecause 30000 does not satisfy Salary > 50000.
Why Other Options Are Incorrect:
Option B (Incorrect):JOIN VIEWS isnot a valid SQL clause.
Option C (Incorrect):MATERIALIZED VIEW refers tostored viewsin some databases, but it doesnotreject incorrect inserts/updates.
Option D (Incorrect):BASE TABLE refers to theoriginal table from which a VIEW is created.
Thus, the correct answer is WITH CHECK OPTION, whichensures that only valid data modifications occur.
