Given the following two tables:TAB1 R1A A A B B C C D E TAB2 R2A A B B C C DWhich of the following queries returns the following result set? RETVAL E()A.SELECT r1 AS retval FROM tab1 INTERSECT SELECT r2 AS retval FROM tab2B.SELECT r1 AS retval FROM tab1 E

题目
Given the following two tables:TAB1 R1A A A B B C C D E TAB2 R2A A B B C C DWhich of the following queries returns the following result set? RETVAL E()

A.SELECT r1 AS retval FROM tab1 INTERSECT SELECT r2 AS retval FROM tab2

B.SELECT r1 AS retval FROM tab1 EXCEPT SELECT r2 AS retval FROM tab2

C.SELECT DISTINCT r1 AS retval FROM tab1, tab2 WHERE r1 <> r2

D.SELECT r1 AS retval FROM tab1 UNION SELECT r2 AS retval FROM tab2


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1.196. Shoppers who carefully plan their visit to the grocery store can save money on their grocery bills. Shopping when not hungry, sticking to their grocery list, and _1_ a few simple rules will cut down the grocery bill. Shoppers should visit the grocery store on a full stomach by planning their trip _2_ after a large meal. If that’s not possible, they should find something healthy to eat on while preparing a grocery list. Most shoppers are less _3_ to buy extras when they are not troubled by hunger. Although having a list and _4_ to it is the most important factor in saving money, shoppers must prepare lists wisely in order to save. A carefully planned list should _5_ in season produce and any items on sale or discount through coupons. Many special buys are announced through the local newspapers, so buying the “grocery issue” is _6_ the money you spend. What’s more, it’s important to remember that many newer, more expensive products first offered through coupons may not _7_ enough savings for shoppers to give up products they usually buy. Now that the shopper has _8_ the grocery list, it’s time to leave for the store. However, no preparations are complete without a pocket calculator or a piece of paper and a pencil to figure costs. Once at the store, the shopper who wants to save money should follow a few more rules. The shoppers should not stay _9_ than necessary because bills go up each minute the shopper is in the store. So, _10_ a time limit and a cost limit can hold down the bill. [共10题](1)(A) carrying (B) making (C) taking (D) following(2)(A) recently (B) regularly (C) immediately (D) completely(3)(A) willingly (B) likely (C) reluctantly (D) happily(4)(A) sticking (B) replying (C) according (D) belonging(5)(A) keep (B) make (C) increase (D) include(6)(A) worth (B) suitable (C) value (D) fit(7)(A) come from (B) result in (C) succeed in (D) depend on(8)(A) saw (B) taken (C) completed (D) read(9)(A) shorter (B) faster (C) longer (D) quicker(10)(A) setting (B) putting (C) making (D) taking

更多“Given the following two tables:TAB1 R1A A A B B C C D E TAB2 R2A A B B C C DWhich of the following queries returns the following result set? RETVAL E() ”相关问题
  • 第1题:

    Given:11.Stringtest="TestA.TestB.TestC.";12.//insertcodehere13.String[]result=test.split(regex);Whichregularexpression,insertedatline12,correctlysplitstestinto"TestA","TestB",and"TestC"?()

    A.Stringregex="";

    B.Stringregex="";

    C.Stringregex=".*";

    D.Stringregex="\\s";

    E.Stringregex="\\.\\s*";


    参考答案:E

  • 第2题:

    根据下面资料,回答
    I grew up in a community called Estepona. I was 16 when one morning my Dad told me I could drive him into a 16 village called Mijas, on condition that I took the car in to be 17 at a nearby garage. I readily accepted. I drove Dad into Mijas, and 18 to pick him up at 4 p.m. then dropped off the car at the 19 . With several hours to spare, I went to a theater 20 , when the last movie finished, it was six. I was two hours late!
    I knew Dad would be angry if he 21 I′d been watching movies. So I decided not to tell him the truth. When I 22 there I apologized for being late, and told him I′ d 23 as quickly as I could, but that the car had needed a major repairs. I′ll never forget the 24 he gave me. "I′m disappointed you 25 you have to lie to me, Jason." Dad looked at me again. "When you didn′t 26 , I called the garage to ask if there were any 27 , and they told me you hadn′t yet picked up the car." I felt 28 as I weakly told him the real reason. A 29 passed through Dad as he listened attentively. "I′m angry with 30 . I realize I′ve failed as a father. I′m going to walk home now and think seriously about 31 I′ve gone wrong all these years." "But Dad, it′s 18 miles!" My protests and apologies were 32 . Dad walked home that day. I drove behind him, 33 him all the way, but he walked silently.
    Seeing Dad in so much 34 and emotional pain was my most painful experience. However, it was 35 the most successful lesson. I have never lied since.
    第(33)题选

    A.asking
    B.persuading
    C.begging
    D.following

    答案:C
    解析:
    考查词义辨析。ask“要求”,persuade“劝说”,beg“乞求”,follow“跟随”。C项最符合文意,“我”犯了错,想乞求父亲上车。

  • 第3题:

    共用题干
    Vibrating Rubber Celiphones

    Vibrating rubber celiphones could be the next big thing in mobile communications.They allow people to press the phone to transmit vibrations along with their______(51)words.According to a research team at the MIT Media Lab in Cambridge,Massachusetts,the idea will make______ (52)more fun.
    Many mobile phones can already vibrate instead of ringing______(53)you do not want people to know you are getting a call. "But these______ (54) are too simple for subtle(敏感的) communication".______(55)Angela Chang of the lab's Tangible Media Group."They're either on or off,"she says.
    But when you hold Chang's rubber cellphone your fingers and thumb wrap around five ______(56)speakers. They vibrate______(57)your skin around 250 times per second.Beneath these speakers sit pressure sensors(传感器),so you can transmit vibration as well as ______(58)it. When you squeeze with a finger,a vibration signal is transmitted______(59) your caller's corresponding finger,its speed______(60)on how hard you squeeze.
    Chang says that within a few minutes of being given the phones,students were using the vibration feature to______(61)emphasis to what they were saying. Over time,people even began to transmit their own kind of ad hoc(特别的)" Morse code " , which they would repeat back to show they were______(62)what the other person was saying.
    Chang thinks"vibralanguages"could function for the same______(63)as texting:sometimes people want to communicate______(64)without everyone nearby knowing what they're saying."And______(65)actually being able to shake someone's hand when you close a business deal,"she says.

    _________(62)
    A:controlling
    B:asking
    C:discussing
    D:following

    答案:D
    解析:
    words只能用spoken来修饰。
    phoning的含义是打电话,符合题意。
    该句指出,当人们不希望别人知道有电话打进来的时候,会选择振动,而非响铃。故D选项符合题意。
    上句提到用振动代替响铃,因此,此空应是上文的重复。
    根据上下文和语法可知答案为B。
    选项tiny意思为“微小的,小型的”。联系上下文,应该选择C项。loud speakers意思是“扬声器”。
    此处的意思是“与皮肤之间的振动”,其他几个选项都不符合题意。
    此处的意思是“你可以接收振动”,因此选择receive“接收”。
    transmit to为固定搭配,意思为“传送到”。
    depend on为固定搭配,意思为“有赖于,依靠”。
    add…to…意思为“把……加到……中”。
    following的含义为“跟得上,听得懂”。此处的含义是听得懂其他人所说的话。其他几项均不符合题意。
    the same reason意为“相同的原因”。其他几项均不符合题意。
    此处的含义是“交流一些事情”。其他几项均无此含义。
    这里的意思是“想象一下”。四个选项中,只有imagine可以合乎上下文。

  • 第4题:

    [A] set [B] exact [C] given [D] placed


    正确答案:A

  • 第5题:

    Higher cognitive abilities may come with a pitfall-a susceptibility to judging people based on stereotypes.A new study from New York University l that highly intelligent people are quicker to learn stereotypes and base decisions off them.It may come down 2 someone's ability to detect and encode patterns.It's not all bad news 3,as these high-intelligence people are likely to quickly update and 4 their ideas on stereotypes when introduced to new information.For the study,1,257 individuals were shown a(n)5 0f computerized male faces that were paired with a description of past behavior,either positive or negative However,the researchers manipulated avatar faces 6 people with noses that were purposely wider were associated with negative traits,7.those with more narrow noses were associated with positive traits.8this,individuals were asked to complete a task in 9 they had to trust an individual online who was represented by an avatar face 10 those the volunteers were shown in the trait association task.Individuals who 11 higher on pattern detection,12 0f higher intelligence,were also more likely to associate wider noses with negative traits,and were 13 likely to trust wide-nosed avatars in the final task.Pattern detection is an essential part of human intelligence,and is one of the main features that helped our brains evolve 14 what they are today,but the skill has its limits."Finding that higher pattern detection ability 15 people at greater risk to detect and apply stereotypes,but also to reverse them,implicates this ability as a cognitive mechanism 16 stereotyping,"added co-author Jonathan Freeman in a statement.While stereotypes can be useful and a way to avoid danger,17 associating police officers with safety or gunmen with danger,there are pitfalls t0 18 people based on a generally held idea.Stereotypes cause you to judge people 19.knowing anything about them-we wouldn't want others to do that to us,20 why not afford them the same Courtesy 8选?

    A.Finishing
    B.Accompanying
    C.Preceding
    D.Following

    答案:D
    解析:
    本题考查上下文语义十动词辨析。空格句指出,研究对象要完成一项任务:从用户头像中选出可信任的在线用户;而上文是“研究人员向研究对象展示一些提前设计好与某种特质挂钩的男性头像”,“被展示头像”一“从头像中选出……”很明显是先后发生的关系,D.Following符合文意。A.Finishing的逻辑主语为主句主语Individuals,而空格词的宾语this回指上句researchers的动作,语义不通,且该词表达先后顺序时一般用于人fter finishing this结构中。

  • 第6题:

    4、下面的程序是否能够正常执行,若不能,请解释原因;若能,请分析其执行结果。 from random import randint result = set() while True: result.add(randint(1,10)) if len(result)==20: break print(result)


    无法正确执行,因为该程序的功能是从[1,10]区间中选择20个不同的随机整数,而该区间并没有这么多整数,所以程序死循环。