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You created a view called EMP_DEPT_VU that contains three columns from the EMPLO

You created a view called EMP_DEPT_VU that contains three columns from the EMPLOYEES and DEPARTMENTS tables:EMPLOYEE_ID, EMPLOYEE_NAME AND DEPARTMENT_NAME.The DEPARTMENT_ID column of the EMPLOYEES table is the foreign key to the primary keyDEPARTMENT_ID column of the DEPARTMENTS table.You want to modify the view by adding a fourth column, MANAGER_ID of NUMBER data type from the EMPLOYEES tables.How can you accomplish this task? ()

A. ALTER VIEW EMP_dept_vu (ADD manger_id NUMBER);

B. MODIFY VIEW EMP_dept_vu (ADD manger_id NUMBER);

C. ALTER VIEW emp_dept_vu AS SELECT employee_id, employee_name, department_name, manager_id FROM employee e, departments d WHERE e.department _ id = d.department_id;

D. MODIFY VIEW emp_dept_vu AS SELECT employee_id, employee_name, department_name, manager_id FROM employees e, departments d WHERE e.department _ id = d.department_id;

E. CREATE OR REPLACE VIEW emp_dept_vu AS SELECT employee_id, employee_name, department_name, manager_id FROM employees e, departments d WHERE e.department _ id = d.department_id;

F. You must remove the existing view first, and then run the CREATE VIEW command with a new column list to modify a view.

正确答案:

参考E

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