Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer.
Section 1
1.
If a database administrator wants to ensure that changes performed through a view do not violate existing constraints, which clause should he/she include when creating the view?
Mark for Review (1) Points
WITH READ ONLY
FORCE
WITH CONSTRAINT CHECK
WITH CHECK OPTION (*)
Correct
2.
Given the following view what operations would be allowed on the emp_dept view:
CREATE OR REPLACE VIEW emp_dept AS SELECT SUBSTR(e.first_name,1,1) ||' '||e.last_name emp_name, e.salary, e.hire_date, d.department_name FROM employees e, departments d WHERE e.department_id = d.department_id AND d.department_id >=50;
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SELECT, DELETE
SELECT, UPDATE of all columns
SELECT, UPDATE of some columns, DELETE (*)
SELECT, INSERT
Correct
3.
There is only one kind view? True or False?
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True
False (*)
Correct
4.
Which of the following DML operations is not allowed when using a Simple View created with read only?
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INSERT
UPDATE
DELETE
All of the above (*)
Correct
5.
Examine the view below and choose the operation that CANNOT be performed on it.
CREATE VIEW dj_view (last_name, number_events) AS SELECT c.last_name, COUNT(e.name) FROM d_clients c, d_events e WHERE c.client_number = e.client_number GROUP BY c.last_name
Mark for Review (1) Points
CREATE OR REPLACE dj_view (last_name, number_events) AS SELECT c.last_name, COUNT(e.name) FROM d_clients c, d_events e WHERE c.client_number = e.client_number GROUP BY c.last_name;
INSERT INTO dj_view VALUES ('Turner', 8); (*)
SELECT last_name, number_events FROM dj_view;
DROP VIEW dj_view;
Correct
6.
Using the pseudocolumn ROWNUM in a view has no implications on the ability to do DML's through the view. True or False?
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