QUESTION NO: 57
Examine the structure of the MARKS table:
Exhibit:
Which two statements would execute successfully? (Choose two.)
A. SELECT student_name,subject1
FROM marks
WHERE subject1 > AVG(subject1);
B. SELECT student_name,SUM(subject1)
FROM marks
WHERE student_name LIKE 'R%';
C. SELECT SUM(subject1+subject2+subject3)
FROM marks
WHERE student_name IS NULL;
D. SELECT SUM(DISTINCT NVL(subject1,0)), MAX(subject1)
FROM marks
WHERE subject1 > subject2;
Answer: C,D
答案解析：
参考：109：http://blog.csdn.net/rlhua/article/details/11974623
Explanation: