单项选择题
A.SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester_end DESC, gpa DESC;
B.SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester _end, ASC,gpa ASC;
C.SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester _end, gpa DESC;
D.SELECT student_id, semester_end, gpa FROM student_grades ORDER BY gpa DESC,semester_end DESC;
E.SELECT student_id, semester_end, gpa FROM student_grades
单项选择题 In a SELECT statement that includes a WHERE clause, where is the GROUP BY clause placed in the SELECT statement?（）
多项选择题 Examine the SQL statements that creates ORDERS table: For which columns would an index be automatically created when you execute the above SQL statement? （）
单项选择题 Examine the data of the EMPLOYEES table. EMPLOYEES (EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID) EMP_NAME DEPT_ID MGR_ID JOB_ID SALARY EMPLOYEE_ID 101 Smith 20 120 SA_REP 4000 102 Martin 10 105 CLERK 2500 103 Chris 20 120 IT_ADMIN 4200 104 John 30 108 HR_CLERK 2500 105 Diana 30 108 HR_MGR 5000 106 Bryan 40 110 AD_ASST 3000 108 Jennifer 30 110 HR_DIR 6500 110 Bob 40 EX_DIR 8000 120 Ravi 20 110 SA_DIR 6500 Which statement lists the ID, name, and salary of the employee, and the ID and name of the employees manager, for all the employees who have a manager and earn more than 4000?（）