试题二 阅读以下说明，根据要求回答下列问题。 [说明] 某航空公司要开发一个订票信息处理系统，该系统的部分关系模式如下： 航班(航班编号，航空公司，起飞地，起飞时间，目的地，到达时间，票价) 折扣(航班编号，开始日期，结束日期，折扣) 旅客(身份证号，姓名，性别，出生日期，电话，VIP折扣) 购票(购票单号，身份证号，航班编号，搭乘日期，购票金额) 有关关系模式的属性及相关说明如下： (1)航班表中的起飞时间和到达时间不包含日期，同一航班不会在一天出现两次及两次以上； (2)各航空公司会根据旅客出行淡旺季适时调整机票的折扣，旅客购买机票的购票金额计算公式为：票价×折扣×VIP折扣，其中旅客的VIP折扣与该旅客已购买过的机票的购票金额总和相关，在旅客每次购票后被修改。VIP折扣值的计算由函数float vip_value(char[18]身份证号)完成。 根据以上描述，回答下列问题。
请将如下SQL语句的空缺部分补充完整。
(1)查询搭乘日期在2012年1月1日至2012年12月31日之间，且合计购票金额大于等于10000元的所有旅客的身份证号、姓名和购票金额总和，并按购票金额总和降序输出。
SELECT 旅客.身份证号,姓名,SUM(购票金额)
FROM 旅客,购票
WHERE ______
GROUP BY ______;
ORDER BY ______;
(2)经过中转的航班与相同始发地和目的地的直达航班相比，会享受更低的折扣。查询从广州到北京，经过一次中转的所有航班对，输出广州到中转地的航班编号、中转地、中转地到北京的航班编号。
SELECT ______
FROM 航班航班1,航班 航班2
WHERE ______;
The Amundsen-Scott South Pole Station made headlines in April when the doctor for that remote science facility was taken seriously ill in the middle of the dark, frigid Antarctic winter. Thankfully, Canadian pilots successfully evacuated the stricken physician—but he was not all that was ailing at the bottom of the world. The station itself has been deteriorating for years, prompting the National Science Foundation to begin this past year a $153 million modernization, which should be completed by early 2006. (66) But construction at this remote site is no small task. All materials have to be carried in by air from McMurdo Station on the coast using special ski-equipped transport planes. And workers have to contend with temperatures that average around -32 degrees Celsius over the summer months. (67) The South Pole also provides astrophysicists with a remarkable laboratory to study high-energy neutrinos: AMANDA (Antarctic Muon and Neutrino Detector Array) uses deeply buried
A. One such place is Dome C (located in the Australian sector, at roughly 73 degrees South latitude), where French and Italian scientists are now setting up a permanent base, called Concordia Station.
B. The logistical difficulties and great expense prompt one to ask. Why maintain a permanent science base at the South Pole at all One answer is that certain kinds of research can be done in no other spot. In particular, the South Pole is said to offer an ideal setting for astronomers, because the air is exceptionally cold, thin and dry, making this locale the next best place for sitting a telescope.
C. European and Australian astronomers are indeed quite interested in the opportunities that Dome C affords. Still, U.S. participation will probably not amount to much, because, as Bally notes, "the U.S. has put all its eggs in the South Pole." This strategy is hard to defend on the basis of doing the best astronomy, the discipline most often cited in official statements about the scientific importance of Amundsen-Scott Station.
D. The submillimeter to millimeter-scale observations are, however, critical to the study of the cosmic microwave background radiation, and they are useful, too, for examining molecular clouds in stellar nurseries.
E. Also, the air at the South Pole is, in fact, not so perfect for astronomy, because it is colder at the surface than a few hundred meters above. John Bally, an astronomer now at the University of Colorado, Boulder, who was responsible for site testing at the South Pole, points out that this temperature inversion combined with the stiff winds there give rise to a turbulent layer of air that blurs optical and infrared images. Bally also notes that there is a perpetual ice fog at the South Pole in winter and that the base is situated on the auroral circle, the locus where charged particles in the upper atmosphere light up the sky most intensely: "You would not go about picking astronomical sites the way this was done."
F. Built in the 1970s to replace an even older South Pole base (which is now buried under nine meters of snow), the Amundsen-Scott Station consists of a large geodesic dome and several smaller outbuildings. The dome is half-buried in drifts and suffers from an unstable foundation that threatens its integrity. Many other parts of the infrastructure—from fuel distribution to waste disposal—are also in dire need of refurbishment.
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