ocp 11g认证题库大全：1Z0-051-109题
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ocp 11g认证题库大全：1Z0-051-109题，完整题库请点击这里联系老师咨询了解
109. Examine the structure of the MARKS table:
name Null Type
STUDENT_ID NOT NULL VARCHAR2(4)
STUDENT_NAME VARCHAR2(25)
SUBJECT1 NUMBER(3)
SUBJECT2 NUMBER(3)
SUBJECT3 NUMBER(3)
Which two statements would execute successfully? (Choose two.)
A. SELECT student_name,subject1
FROM marks
WHERE subject1 > AVG(subject1); where不能跟表达式
B. SELECT student_name,SUM(subject1)
FROM marks
WHERE student_name LIKE 'R%'; 少了group by
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: CD
试题解析：
A答案：AGV分组函数不能用在where子句里
B答案：缺少group by
C答案：因为测试数据里没有student_name没有为空的，所有无返回值。
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