单项选择题
A.SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL;
B.SELECT (gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;
C.SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL GROUP BY semester_end;
D.SELECT MAX(gpa) GROUP BY semester_end WHERE gpa IS NOT NULL FROM student_grades;
E.SELECT MAX(gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;
多项选择题 Which three are DATETIME data types that can be used when specifying column definitions? （）
单项选择题 Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE Which UPDATE statement is valid?（）
单项选择题 Examine the structure of the EMPLOYEES and DEPARTMENTS tables: EMPLOYEES EMPLOYEE_ID NUMBER DEPARTMENT_ID NUMBER MANAGER_ID NUMBER LAST_NAME VARCHAR2(25) DEPARTMENTS DEPARTMENT_ID NUMBER MANAGER_ID NUMBER DEPARTMENT_NAME VARCHAR2(35) LOCATION_ID NUMBER You want to create a report displaying employee last names, department names, and locations. Which query should you use?（）