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问题 填空题

在SQL的CREATE TABLE语句中，为属性说明取值范围(约束)的是______短语。

答案

参考答案：CHECK

解析： 本题是对SQL的CREATE TABLE命令的考查，命令中定义域完整性的约束规则是CHECK短语。

单项选择题

Asherman综合征是指

A．先天性无子宫内膜

B．产后大出血引起的闭经

C．睾丸女性化综合征

D．人流手术操作不当、造成宫腔粘连性闭经

E．垂体肿瘤所致闭经
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单项选择题

Questions from 36 to 40 are based on the following passage: There are a lot of “markets”. Some markets are local; you may be willing to compare prices for fruits and vegetables in a few shops in your local area, but you would be unwilling to go across the city to find out more information. Some markets are national. Many firms sell goods across the country. Some markets are global or international. Increasingly, more and more countries are involved in the world economy, whether they know about it or not.However, there are many other markets: labor markets for job seekers, supermarkets for grocery shopping, foreign exchange market, capital market, real estate markets and so on. And we must not overlook the fact that many services such as banking, insurance are also bought and sold on a worldwide scale. But what is a “market” Most people would say, “A market is a place where enough buyers and sellers meet face to face, so that a market price for goods and services can be determined.” However, with rapid growth of telecommunications, it is no longer necessary for buyers and sellers to physically meet to form a market.You may hear the terms “global market” or “global economy”. What do those terms mean to you What do they mean to business today Thanks to the Information Age we are seconds away from the rest of world. Business everywhere recognizes that they can expand their market to anywhere and do business at any time because of the Internet. Now, the Internet is the fastest growing market in the world today, yet buyers and sellers don’t even have to leave their own homes to transact business.In the modern world, a market can take many forms. Generally speaking, a market may be housed in a place, or it may exist only in people’s minds. And a market can be any place or process that brings together buyers and sellers with a view to agreeing to a price.

The stock market, banking services market and capital market can be described as（）.

A．supermarket　

B．financial market

C．labor market　

D．real estate market
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