【单选题】
Examine the data in the EMPLOYEES and DEPARTMENTS tables:<br /> EMPLOYEES<br /> EMP_NAME DEPT_ID MGR_ID JOB_ID SALARY<br /> EMPLOYEE_ID<br /> 101 Smith 20 120 SA_REP 4000<br /> 102 Martin 10 105 CLERK 2500<br /> 103 Chris 20 120 IT_ADMIN 4200<br /> 104 John 30 108 HR_CLERK 2500<br /> 105 Diana 30 108 IT_ADMIN 5000<br /> 106 Smith 40 110 AD_ASST 3000<br /> 108 Jennifer 30 110 HR_DIR 6500<br /> 110 Bob 40 EX_DIR 8000<br /> 120 Ravi 20 110 SA*DIR 6500<br /> DEPARTMENTS<br /> DEPARTMENT_ID DEPARTMENT_NAME<br /> 10 Admin<br /> 20 Education<br /> 30 IT<br /> 40 Human Resources<br /> Also examine the SQL statements that create the EMPLOYEES and DEPARTMENTS tables:<br /> CREATE TABLE departments<br /> (department_id NUMBER PRIMARY KEY,<br /> department _ name VARCHAR2(30));<br /> CREATE TABLE employees<br /> (EMPLOYEE_ID NUMBER PRIMARY KEY,<br /> EMP_NAME VARCHAR2(20),<br /> DEPT_ID NUMBER REFERENCES<br /> departments(department_id),<br /> MGR_ID NUMBER REFERENCES<br /> employees(employee id)
A、Only the row with department ID 40 is deleted in the DEPARTMENTS table.
B、The statement fails because there are child records in the EMPLOYEES table with department ID 40.
C、The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 110 and 106 are deleted from the EMPLOYEES table.
D、The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 106 and 110 and the employees working under employee 110 are deleted from the EMPLOYEES table.
E、The row with department ID 40 is deleted in the DEPARTMENTS table. Also all the rows in the EMPLOYEES table are deleted.
F、The statement fails because there are no columns specifies in the DELETE clause of the DELETE statement.
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