单项选择题

SQL语言是一种(96)语言,其主要功能有(97),它的典型句型为;
SELECT A1,A2,...An
FROM R1,R2,...Rm
WHERE F
其中Ai(i=1,2,…,n)、Rj(j=1,2,…,m)和F分别是(98)。
关系模式学生成绩表(S#,C#,Score)中S#是学生的学号,C#是课程号,Score是学号为S#学生的C#号课程的成绩。若要查询每门课程的平均成绩,且要求查询结果按平均成绩升序排列,平均成绩相同时,按课程号降序排列,可用SQL,语言写为(99)。若查询的结果仅限于平均分数超过85分的,则应(100)。
A.函数型
B.关系数据库
C.人工智能
D.高级算法

A...An
B...Rm
C.函数型
B.关系数据库
C.人工智能
D.高级算法
题目列表

你可能感兴趣的试题

单项选择题

【案例分析题】

When your family wants to buy or replace a car,a television,or a washing machine,you find the money either from savings or by borrowing from the bank,a hire-purchase company or perhaps a friend.Similarly,a family buying a house for the first time commonly borrows from a building society(住宅互助委员会).
If you own a private business,a garage,shop,or a farm,you will need,from time to time,to buy new equipment,new furnishings,or,if you are doing well,new premises(房屋)so that you can expand.Some of the cost you can meet from the profits you have kept in the business,but often you will need help.
You will go to your bank,to a finance house,or perhaps to a relative or friend for finance provided from his savings.When you borrow money or raise money in this way you pay it back out of future profits.
Many large businesses,however,need cash for new developments or expansion far in excess of what can be provided from their profits or from private sources of capital.A new factory,an oil-well in the North Sea,can cost millions of pounds to construct and bring into production;a new design of car or brand of medicine likewise can cost millions of pounds to design,develop,test and market before it reaches the stage where it earns a profit.
Often these costs can be met from profits earned in other parts of the business or from reserves built up from profits earned in past years.Sometimes,however,it is necessary,and often it may be more advantageous,to raise new money from other sources.
There can be little prospect of raising the sort of stuns needed by major businesses from friends or acquaintances,and generally the banks are reluctant to provide sufficient cash on a permanent basis for long-term projects,though they will provide short-term finance.Such companies can sometimes only raise the money they need to stay in the front of industry and develop new products and sources of production by turning to the public at large and inviting it to lend them cash or take a share in the business in exchange for a share in future profits.This they can do by offering shares in the business or loan capital through stock exchange(证券交易所).

If you want to buy a house, which of the following could you do?()

A.Borrow the money from a building society.
B.Borrow the money from a bank.
C.Take money from your savings.
D.Ask a friend to help you out.

微信扫码免费搜题