题目内容
在“学生—选课—课程”数据库中的三个关系如下：
S(SNO,SNAME,SEX,AGE),
SC(SNO,CNO,GRADE),
C(CNO,CNAME,TEACHER)。
查找选修“数据库技术”这门课的学生的学生姓名和成绩。若使用连接查询的SQL语句是：SELECT SNAME,GRADE FROM S,SC,C WHERE子句。其中的WHERE子句应该是A)CNAME=′数据库技术′AND S.SNO=SC.SNO AND SC.CNO=C.CNOB)CNAME=′数据库技术′AND S.SNO=SC.SNO AND SC.CNO=CNOC)CNAME=数据库技术 AND S.SNO=SC.SNO AND SC.CNO=C.CNOD)CNAME=′数据库技术′AND S.SNO=SC.SNO
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This question is interest for a number of reasons. Apart from curiosity about the level of animals' understanding, research on self-recognition in animals has several benefits. It provides some insight into the evolutionary significance of this skill of self-recognition and into the level and kinds of cognitive competence that the skill requires. Such research also indicates the kinds of learning experiences that determine the development of self-recognition. In addition, work with animals fosters the use of techniques that are not dependent on verbal responses and that may therefore be suitable for use with preverbal children.
The evidence indicates that dogs and almost all other nonhumans do not recognize themselves. In a series of clever experiments, however, Gallup has shown that the chimpanzee does have this capacity. Gallup exposed chimpanzees in a small cage to a full-length mirror for ten consecutive days. It was observed that over this period of time the number of self-directed responses increased. These behaviors included grooming parts of the body while watching the results, guiding fingers in the mirror, and picking at teeth with the aid of the mirror. Describing one chimp, Gallup said, "Marge used the mirror to play with and inspect the bottom of her feet; she also looked at herself upside down in the mirror while suspended by her feet from the top of the cage; she was also observed to stuff celery leaves up her nose using the mirror for purposes of visually guiding the stems into each nostril."
Then the researchers devised a further test of self-recognition. The chimps were anesthetized and marks were placed over their eyebrows and behind their ears, areas the chimps could not directly observe. The mirror was temporarily removed from the cage, and baseline data regarding their attempts to touch these areas were recorded. The data clearly suggest that chimps do recognize themselves, or are self-aware, for their attempts to touch the marks increased when they viewed themselves. Citing further evidence for this argument, Gallup noted that chimpanzees with no prior mirror experience did not direct behavior. to the marks when they were first exposed to the mirror; that is, the other chimpanzees appeared to have remembered what they looked like and do have responded to the marks because they noticed changes in their appearance.
The idea of this passage is to discuss______.
The "school community"(Line ,. Para. 3)the author refers to would probably include ______.
There are two ways to defend the deal. One is to point out its advantages, which is what Ms Fiorina did this week. Merging with Compaq, she said, would enable HP to reach its goals faster than it could on its own. The deal would improve HP's position in key markets such as storage and high-end computing, as well as the economics of its PC business. It would double the size of HP's sales force and broaden its customer base, providing more potential clients for its services and consulting arms. It would improve cashflow, margins and efficiency by adding "breadth and depth" to HP. "Having spent the last several months planning the integration of these two companies, we are even more convinced of the power of this combination," Ms Fiorina concluded.
It sounds too good to be true, and it almost certainly is. But the other way to defend the deal is to point out that, even if it was a bad idea to start with, abandoning it could be even worse—a view that, unsurprisingly, Ms Fiorina chose not to advance, but is being quietly put forward by the deal's supporters.
Scrapping the merger would be extremely painful for a number of reasons. Since the executive teams of both firms have committed themselves to the deal, they would be utterly discredited if it fell apart, and would probably have to go. Under the terms of the merger agreement, HP might have to pay Compaq as much as $675m if it backed out. The two firms would be considerably weakened; they would also be rivals again, despite having shared confidential technical and marketing information with each other over the past few months. In short, it would all be horribly messy. What can be done to save the deal？ Part of the problem is that HP has no plan B. "They need a brand-recovery effort immediately," says one industry analyst. HP must give the impression that it is strong and vital, rather than desperate, and that its future is not dependent on the deal going forward. That could make the merger look more attractive and bring investors back on board.
This week's results will certainly help. The David and Lucile Packard Foundation, which owns just over one-tenth of HP's shares, will decide whether to back the merger in the next few weeks, and HP's shareholders are to vote on it early next year. The more credible HP's plan B, the less likely it is that it will be needed.
What is Ms Fiorina's attitude toward the merging of HP and Compaq？
The main idea of these business-school academics is appealing. In a word where companies must adapt to new technologies and source of competition, it is much harder than it used to be to offer good employees job security and an opportunity to climb the corporate ladder. Yet it is also more necessary than ever for employees to invest in better skills and sparkle with bright ideas. How can firms get the most out of people if they can no longer offer them protection and promotion？
Many bosses would love to have an answer. Sumantrra Ghoshal of the London Business School and Christopher Bartlett of the Harvard Business School think they have one: "Employability." If managers offer the right of training and guidance, and change their attitude towards their underlings, they will be able to reassure their employees that they will always have the skills and experience to find a good job—even if it is with a different company.
Unfortunately, they promise more than they deliver. Their thoughts on what an ideal organization should accomplish are hard to quarrel with: encourage people to be creative, make sure the gains from creativity are shared with the pains of the business that can make the most of them, keep the organization from getting stale and so forth. The real disappointment comes when they attempt to show how firms might actually create such an environment. At its nub is the notion that companies can attain their elusive goals by changing their implicit contract with individual workers, and treating them as a source of value rather than a cog in a machine.
The authors offer a few inspiring example of companies—they include Motorola, 3M and ABB—that have managed to go some way towards creating such organizations. But they offer little useful guidance on how to go about it, and leave the biggest questions unanswered. How do you continuously train people, without diverting them from their everyday job of making the business more profitable？ How do you train people to be successful elsewhere while still encouraging them to make big commitments to your own firm？ How do you get your newly liberated employees to spend their time on ideas that create value, and not simply on those they enjoy？ Most of their answers are platitudinous, and when they are not they are unconvincing.
We can infer from the passage that in the past an employee______.
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