题目内容
（请给出正确答案）
A.陈述A正确，陈述B错误
B.都是正确的
C.都是错误的
D.陈述A错误，陈述B正确
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更多“陈述A：SubQuery1 UNION SubQuery2语句，其中SubQuery1和SubQuery2查询中相应的列必须以同一顺序出现。 陈述B：GROUP BY和HAVING子句不能在子查询中使…”相关的问题
A、CREATE VIEW S_MALE(学号,姓名) AS SELECT 学号,姓名 FROM student WHERE 班号='09031'
B、CREATE VIEW S_G(学号,姓名,课程名,分数) AS SELECT S.学号,姓名,课程名,分数 FROM student S,score SC,course C WHERE S.学号=SC. 学号AND SC. 课程号 = C. 课程号
C、CREATE VIEW S_AVG(学号,平均分) AS SELECT 学号,AVG(分数) FROM score WHERE 分数IS NOT NULL GROUP BY 学号
D、CREATE VIEW S_FEMALE(姓名,出生日期) AS SELECT 姓名,出生日期 FROM student WHERE 性别='女'
A、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade DESC
B、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade
C、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 HAVING COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC
D、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 and COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC
A、SELECT S# FROM SC WHERE C#='C2' AND GRADE >= ALL(SELECT GRADE FROM SC WHERE C#='C2')
B、SELECT S# FROM SC WHERE C#='C2' AND GRADE >=(SELECT GRADE FROM SC WHERE C#='C2')
C、SELECT S# FROM SC WHERE C#='C2' AND GRADE IN (SELECT GRADE FROM SC WHERE C#='C2')
D、SELECT S# FROM SC WHERE C#='C2' AND GRADE NOT IN(SELECT GRADE FROM SC WHERE C#='C2')
A、对于由单一Table子集构成的视图，即如果视图是从单个基本表使用选择、投影操作导出的，并且包含了基本表的主键，则不能更新
B、如果视图的select目标列包含聚集函数，则不能更新
C、如果视图中包括了group by子句，则不能更新
D、如果视图是由单个表的列构成，但并没有包括主键，则不能更新
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