设有学生实体Students(学号,姓名,性别,年龄,家庭住址,家庭成员,关系,联系电话),其中“家庭住址”记录了邮编、省、市、街道信息;“家庭成员,关系,联系电话”分别记录了学生亲属的姓名、与学生的关系以及联系电话。学生实体Students中的“家庭住址”是一个 (64) 属性;为使数据库模式设计更合理,对于关系模式Students (65) 。 65()
A. 可以不作任何处理,因为该关系模式达到了3NF
B. 只允许记录一个亲属的姓名、与学生的关系以及联系电话的信息
C. 需要对关系模式Students增加若干组家庭成员、关系及联系电话字段
D. 应该将家庭成员、关系及联系电话加上学生号,设计成为一个独立的实体
第三篇 Youth Emancipation in Spain The Spanish Government is so worried about the number of young adults still living with their parents that it has decided to help them leave the nest. Around 55 percent of people aged 18-34 in Spain still sleep in their parents’ homes, says the latest report from the country’s state-run Institute of Youth. To coax (劝诱) young people from their homes, the Institute started a "Youth Emancipation (解放)" program this month. The program offers guidance in finding rooms and jobs. Economists blame young people’s family dependence on the precarious (不稳定的) labor market and increasing housing prices. Housing prices have risen 17 percent a year since 2000. Cultural reasons also contribute to the problem, say sociologists (社会学家). Family ties in south Europe - Italy, Portugal and Greece - are stronger than those in middle and north Europe, said Spanish sociologist Almudena Moreno Minguez in her report "The Late Emancipation of Spanish Youth: Key for Understanding". "In general, young people in Spain firmly believe in the family as the main body around which their private life is organized," said Minguez. In Spain - especially in the countryside, it is not uncommon to find entire groups of aunts, uncles, cousins, nieces and nephews (外侄/侄子) all living on the same street. They regularly get together for Sunday dinner. Parents’ tolerance is another factor. Spanish parents accept late-night partying and are wary of setting bedtime rules. "A child can arrive home at whatever time he wants. If parents complain he’ll put up a fight and call the father a fascist," said Jose Antonio G6mez Yanez, a sociologist at Carlos III University in Madrid. Mothers’ willingness to do children’s household chores (家务) worsens the problem. Dionisio Masso, a 60-year-old in Madrid, has three children in their 20s. The eldest, 28, has a girlfriend and a job. But life with mum is good. "His mum does the wash and cooks for him; in the end, he lives well," Masso said. The "Youth Emancipation" program aims at helping young people
A. fight for freedom.
B. live in an independent way.
C. fight against social injustice.
D. get rid of family responsibilities.