题目内容
假设图书管理数据库中有3个表，图书.dbf、读者．dbf和借阅．dbf。它们的结构分别如下： 图书(总编号C(6)，分类号C(8)，书名C(16)，出版单位C(20)，单价N(6,2)) 读者(借书证号C(4)，单位C(8)，姓名C(6)，性别C(2)，职称C(6)，地址C(20)) 借阅(借书证号C(4)，总编号C(6)，借书日期D(8)) 在上述图书管理数据库中，图书的主索引是总编号，读者的主索引是借书证号，借阅的主索引应该是______。
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The new prestige of the British graduates is the most spectacular because in the past Britain has been much 【B1】 interested in universities and degrees than other advanced countries — or even some backward 【B2】 . In 1901 Ramsay Muir observed that Britain had 【B3】 universities per head than any other civilized country in Europe except Turkey. A UNESCO survey in 1967 【B4】 Britain was still close to the bottom in Europe, in 【B5】 of the proportion of the age-group from twenty to twenty-four who were enrolled in 【B6】 education. Most continental countries in the 【B7】 decade have expanded their higher education faster than Britain. University statistics are notoriously difficult to compare, because of the different implications of the word "student" ; in most continental countries anyone who 【B8】 his final school exam — the baccalaureate — is entitled to go into the university on the principle of "let him pass" ; but he has 【B9】 guarantees of tuition or personal attention. Partly as a result there are far more drop-outs and "ghost students" ; in France half the students never become graduates. A comparison of graduates, as opposed 【B10】 students, shows Britain in 【B11】 favorable light, for most British students take a degree. 【B12】 even in terms of graduates, Britain is still 【B13】 in the Europe league. Going to university is a much more solid ambition among the sons of the bourgeoisie in France or Germany than in 【B14】 ; many of the British middle-classes — 【B15】 the shopkeepers and small-business men — have tended to be skeptical, if 【B16】 actually hostile, to university education for their children, and there are still rich and quite intelligent parents who will prefer their children to go straight 【B17】 school into the city, to the army 【B18】 to farming. But the attractions of a BA or 【B19】 MA have penetrated into areas, 【B20】 among the rich and the poor, where they would not have been felt twenty years ago; and they are far-reaching.
设关系模式R上函数依赖集F=A-＞B，B-＞C，C-＞A，则F的最小函数依赖集F1= ______。
Today we take for granted that the mail will be delivered daily at our 71. ______door. But many years ago it might have been placed in a tree trunk and 72. ______underneath a rock. In the early days of the mail no one could be sure aboutwhere or when it will arrive. 73. ______At the southern tip of Africa there was once a post office under a rock.At the old days the route from England to India was around the Cape of 74. ______Good Hope. The journey was stormy and danger. It took six long months. 75. ______Sailors often wished to send mail home, but they seldom met ships boundback to England. So at the cape the sailors would go on ashore. They headed 76. ______for a certain large stone. On the stone scratched the words "Look 77. ______hereunder for letters." They would leave their letters there, knowing that thenext homeward ship would stop and pick it up. 78. ______There was another post office like this at the southern tip of SouthAmerica. During the golden rush days, boats sailed around Cape Horn to 79. ______California. At Cape Horn was a keg(小捅) nailed to a post. Boats comingfrom the east coast would send some sailors to this post office. They pickedup any letters in the keg. At the same time they mailed letters home thatboats sail east could pick up. 80. ______ 78（）
College of Health CareersOverview A coed school founded in 1967 that awards terminal associate degrees. 180 undergraduate students, 86% of freshmen return for a second year.The College Proprietary, on a 1-acre urban campus. Faculty: 23 (13 full-time).Computers: 40 terminals, PCs for student use in computer labs.Undergraduates 180 students from 8 states and territories. 95% women, 0% part-time, 70% state residents, 0% transferred. Fields chosen: 20% health professions and related sciences.Freshmen Application Entrance: moderately difficult. Options: early entrance, deferred entrance. Required: school transcript, recommendations, interview. Recommended SAT I or ACT. Test scores used for admission. Application deadline: rolling. Notification: continuous.Graduation Requirements 158 quarter credits; internship.Expenses Tuition: $5,495 full-time. Tuition guaranteed not to increase for student’’s term of enrollment. College housing not available.College Life Safety: 24-hour emergency response devices.Major Veterinary technology.Bee County CollegeOverview A coed school founded in 1965 that awards associate transfer and terminal degrees. 2,530 undergraduate students. 63% of freshmen return for a second year.The College County-supported, on a 100-acre rural campus. Faculty: 116 (74 full-time). Library: 46,000 books, 326 periodicals, 1,550 records, tapes, and CDs. Computers; 188 terminals, PCs for student use in computer center, computer labs, classrooms, learning resource center, library, learning assistance center.Undergraduates 2,530 students from 17 states and territories, 5 other countries. 60% women, 40% part-time, 9% transferred in, 47% have need-based financial aid. Most Popular recent majors: law enforcement/police sciences, nursing, child care/child and family studies.Freshmen Application Open admission. Options: early entrance, deferred entrance. Required: School transcript, TOEFL for international students. Recommended: SAT I or ACT. Test scores used for counseling/ placement. Application deadline: 8/15.Graduation 55 semester hours; computer course for business, criminalRequirements justice, education, most vocational majors; internship (varies by major).Expenses Area resident tuition: $420 full-time. State resident tuition: $780 full-time. Nonresident tuition: $1,260 full-time. Part-time tuition per semester ranges from $87 to $174 for area residents, $59 to $ 318 for state residents, $252 to $504 for nonresidents. College room and board: $2,220. College room only: $1,060.College Life Drama-theatre group, choral group. Student services; personal-psychological counseling. Safety; controlled dormitory access, room security.Majors Accounting, agricultural sciences, art, biological sciences, business administration, chemistry, child and family studies, computer science, criminal justice, economics, education, engineering, English, finance, French, history, journalism, mathematics, music, nursing, police sciences, political science, sociology, theater.Community CollegeOverview A coed school founded in 1957 that awards associate transfer and terminal degrees. 7,356 undergraduate students.The College State-supported, on a 52-acre urban campus. Faculty; 295 (150 full-time). Library; 50,000 books, 600 periodicals, 400 records, tapes, and CDs, Computers: 175 terminals, PCs for student use in computer center, learning resource center.Undergraduates 7,356 students from 27 states and territories. 63% women, 64% part-time, 97% state residents, 13% transferred in, 9% have need-based financial aid, 2% have non-need-based financial aid, 40% 25 or older, 1% native American, 1% Hispanic, 1% African American, 1% Hispanic, 69% Asian American.Freshmen Application Preference given to state residents. Options: early entrance. Required TOEFL for international students. Required for some: school transcript, recommendations, campus interview. Test scores used for admission. Application deadline: 7/1.Notification: continuous until 8/15.Graduation 60 credits; math/science requirements vary according toRequirements program; proficiency in a foreign language at beginning level; computer course for accounting, marketing, hotel operations, office administration majors; internship.Expenses State resident tuition: $480 full-time, $20 per credit part-time.Nonresident tuition: $2,920 full-time, 122 per credit part-time.Part-time mandatory fees per semester range from $5. 50 to $10.Full-time mandatory fees; $20. Room and board; not available.College Life Orientation program. Choral group, student-run newspaper.Safety: 24 hour patrols.Majors Accounting, arts, data processing, food services management, hotel and restaurant management, legal secretarial studies, liberal arts, marketing, medical assistant technologies, nursing, paralegal studies, physical therapy, secretarial studies/office management. Which college(s) boasts of the largest library collections
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