简述实时ETL的一些难点及其解决办法。
[单选题]If the square root of t is a real number, is the square root of t positive?(1) t＞0(2) t2＞0
[单选题]The author believes the real cause for the increase of divorces today is that______.A．)people have too many sources of entertainmentB．) people have less internal restraintsC．) people no longer enjoy family life as they did beforeD．)people do not want
[单选题]Some argue that by their ______nature, these elite places of learning should not be easily accessible.A． veryB． exactlyC． exactD． just
[单选题]In the spoken English of some areas in the US, the "r" sounds at the end of thewords______.A． are droppedB． dropC． are being droppedD． have dropped
[问答题]Please write an essay in about 150 words entitled “Water Shortage” based on
[试题]We are obliged to them because some of these languages have since vanished, as the peoples who spoke them died out or became assimilated and lost their native languages.
[主观题]It was getting dark． Some children and two Canadian women were still skating near a big hotel． They (36) (have)a good time．A． boy said to his friends，"I (37) (not skate) on a real lake so far．It's wonderful! Look! I (38) (fly)! "Suddenly the ice．b
[单选题]Some officials believe bird flu spread to Africa mainly due to ______.A． the trade of farm birdsB． the waste and liquids of infected birdsC． the fact that sortie people touched sick birds or any infected part of sick birdsD． the virus changed and sta
[单选题]Some people don’t want their names known because they are .A． hesitant to make a donationB． unwilling to draw public attentionC． afraid of an accusationD． ready for involvement
[试题](c) Outline the problems with references. (7 marks)(15 marks)