问题
单项选择题
关系型数据库技术的特征由一下哪些元素确定的？（）
A、行和列
B、节点和分支
C、Blocks和Arrows
D、父类和子类
答案
参考答案：A
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关系型数据库技术的特征由一下哪些元素确定的？（）
A、行和列
B、节点和分支
C、Blocks和Arrows
D、父类和子类
参考答案：A
Text 2
| Of all the truths that this generation of Americans hold self-evident, few are more deeply embedded in the national psyche than the maxim "It pays to go to collage." Since the Gl Bill transformed higher education in the aftermath of W. W. II, a college diploma, once a birthright of the leisured few, has become a lodestone for the upwardly mobile, as integral to the American dream as the pursuit of happiness itself. The numbers tell the story: In 1950s, 43% of high-school graduates went on to pursue some form of higher education; at the same time, only 6% of Americans were college graduates. But by 1992, almost 2 to out of 3 secondary-school graduates were opting for higher education—and 21% of a much larger U.S. population had college diplomas. As Prof. Herbert London of New York University told a commencement audience last June: "The college experience has gone from a rite passage to a right of passage." However, as the class of 1993 is so painfully discovering, while a college diploma remains a requisite credential for ascending the economic ladder, it no longer guarantees the good life. Rarely since the end of the Great Depression has the job outlook for college graduates appeared so bleak: of the 1.1 million students who received their baccalaureate degrees last spring, fewer than 20% had lined up full-time employment by commencement. Indeed, an uncertain job market has precipitated a wave of economic fear and trembling among the young. "Many of my classmates are absolutely terrified," says one of the fortunate few who did manage to land a permanent position. "They wonder if they’ll ever find a job." Some of this recession-induced anxiety will dissipate if a recovery finally begins to generate jobs at what economists consider a normal rate. But the sad fact is that for the foreseeable future, college graduates will be in considerable surplus, enabling employers to require a degree even for jobs for which a college education is really unnecessary. According to Kristina Shelley of the Bureau of Labor Statistics—who bases her estimate on a "moderate projection" of current trends—30 percent of college graduates entering the labor force between now and the year 2005 will be unemployed or will find employment in jobs for which they will be overqualified, joining what economists call the "educationally underutilized". Indeed, it may be quite a while—if ever—before those working temporarily as cocktail waitresses or taxi drivers will be able to pursue their primary career paths. Of course waiting on tables and bustling cab fares are respectable ways to earn a living. But they are not quite what so many young Americans—and their parents—had in mind as the end product of four expensive years in college. |
According to the passage, which of the following is true’
A．A college diploma used to be the privilege of the rich.
B．A college diploma helps one to realize his American dream.
C．College graduates can easily get permanent positions.
D．College graduates are optimistic about their career in the future.