【多选题】【消耗次数：1】
下列关于外键的说法错误的是（ ）
①
A.外键必须和相应的主键同名
②
B.外键值不允许为空
③
C.外键和相应的主键可以不同名，只要定义在相同域上即可
④
D.外键的取值只允许等于所参照关系中某个主键值
参考答案：
复制
纠错
相关题目
【简答题】
如果属性集K是关系模式R的主键，K也是关系模式R2的外键，那么在R2的关系中，K的取值只允许取R的主键或[填空]。
【多选题】
设有课程关系Course（课程号，课程名，学分，开设专业号，先修课程号）和专业关系Speciality（专业号，专业名），则课程关系Course的外键是（ ）
①
A.课程号
②
B.开设专业号
③
C.先修课程号
④
D.学分
【多选题】
设有课程关系Course（课程号，课程名，学分，开设专业号，先修课程号）和专业关系Speciality（专业号，专业名），则课程关系Course的外键是（ ）
①
课程号
②
开设专业号
③
先修课程号
④
学分
【多选题】
营业外收入和营业外支出属于非常项目，必须同时具备以下特征（ ）。
①
引起业务发生的主要原因高度反常
②
业务的发生极其偶然
③
业务的发生具有重大性
④
业务涉及的金额较大
⑤
与日常活动无关
随机题目
【单选题】
An example of dramatic monologue is _____________.
①
Don Juan
②
When We Two Parted
③
My Last Duchess
④
The Waste Land
【单选题】
The heroine Tess in Tess of the Durbervilles seems to be led to her final destruction step by step by ______, as Hardy says at the end of the novel: “Justice was done, and the President of the Immortals had ended his sport with Tess.”
①
Angel Clare
②
Alec
③
Fate
④
Jude
【单选题】
In depiction of his characters, Dickens is famous for_____.
①
those innocent, virtuous, persecuted, hopeless child characters
②
those horrible and grotesque characters
③
those broadly humorous or comical ones
④
all the above
【单选题】
Which of the following writing is not the work by Charles Dickens?
①
Tale of Two Cities
②
Hard Times
③
Oliver Twist
④
Sons and Lovers
【单选题】
Wuthering Heights is known today as __________most fascinating novel.
①
Charlotte Bront?’s
②
Anne Bront?’s
③
Emily Bront?’s
④
George Eliot’s
【单选题】
Hardy’s local-colored works are known as “novels of character and _____.”
①
personality
②
nature
③
domestic life
④
environment
【单选题】
____ is not a Victorian novelist.
①
Charles Dickens
②
George Eliot
③
William Makepeace Thackeray
④
D. H. Lawrence
【单选题】
Chronologically the Victorian period roughly coincides with the reign of Queen _____ who ruled over England from 1836 to 1901.
①
Elizabeth
②
Victoria
③
Mary
④
Anne
【单选题】
Who is the primary narrator of the novel Wuthering Heights?
①
Catherine
②
Heathcliff
③
Nelly
④
Lockwood