题目内容

在修改表时，设置检查约束可以使用的SQL语句是（）

A. Primary Key(主键名)
B. ALTER TABLE 表名 ADD CONSTRAINT 检查约束名 check (约束条件)
C. FOREIGN KEY REFERENCES主键表名（主键字段名）
D. constraint 主键约束名 Primary Key(主键名)

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下列选项中，关于UPDATE语句的描述，正确的是（）

A. UPDATE语句更新数据时可以有条件的更新记录
B. UPDATE只能更新表中的部分记录
C. UPDATE只能更新表中的全部记录
D. 以上说法都不对

数据类型的作用：数据类型决定了数据存储的空间和格式，有助于正确、有效地存储数据。（）

A. 对
B. 错

建立主键的目的就是为了实现实体完整性。（）

A. 对
B. 错

Fill in the blanks with the words given. Change the forms if necessary. Each one can be used only once.terminationslumpdeterioratespiralcomplydrasticlikelihoodevictvergeoriginate1. Brian Wood watched his financial life downward just when he thought he had overcome the obstacles which had been dominating his past.2. A in your confidence may result from your premature optimism about life.3. __ as the measures were, little progress was made in improvement of social order.4. His indulgence in （沉溺于） fun seeking has brought him to the _ of indifference to life.5. In much of the country, abuse of land resulted in a forced ___ of farmers.6. They have got a letter ordering the immediate _ of their occupancy (居住).7. Believe it or not, friendship is apt to ____ in times of crisis.8. I asked the waitress to refill my coffee cup and she happily _ repeatedly until I had consumed enough coffee to stay up all night and study for my exam.9. The way you view the task ahead of you determines your mindset and your of success.10. This type of system which _in the United Kingdom has been widely used throughout Europe.