问题 单项选择题

建立一个基于学生表的查询,要查找出生日期(数据类型为日期/时间型)在2008—01—01和2008—12—31间的学生,在出生日期对应列的准则行中应输入的表达式是( )。

A.Between 2008—01—01 And 2008—12—31

B.Between #2008—01—01 # And # 2008—12—31#

C.Between 2008—01—01 Or 2008—12—31

D.Between # 2008—01—01 # Or # 2008—12—31

答案

参考答案:B

解析: 在Access中,日期型常量要求用“#”括起来;表示区间的关键字用Between…And…。

问答题

A recent study in the United States reports that the family life, education and health of America’s children are generally improving, though child poverty has risen for the first time in a decade, according to the government’s broadest measure of children’s well-being. The report shows that the teenage birth rate is down, young people are less likely to be involved in violent crimes and the death rate for this group has declined. Experts say that teenagers who give birth are less likely to finish high school or to graduate from college than other girls of their age. Also, infants born to teenage mothers are more likely to be of low birth weight, which increases their chances of blindness, deafness, mental retardation, mental illness and cerebral palsy. The study shows that young people were less likely to be victimized in a serious violent crime -- murder, rape, robbery or aggravated assault -- or to commit one. In 2002, there were 11 serious violent crimes per 1,000 people aged 12 to 17, compared with 15 per 1,000 youths in 2001. Child mortality declined, too. In 2000, there were 18 deaths for every 100,000 children aged 5 to 14; a year later, there were 17 deaths for every 100,000 children in this age group. The infant mortality rate slightly increased. Seven of every 1,000 infants died before their first birthday in 2002, compared with a record low of 6.8 per. 1,000 in 2001. Still, children are more likely to be overweight than they were before and child poverty has inched up after several years of decline. The number of overweight children increased to 16 percent between 1999 and 2000, compared with from 11 percent in the early 1990s and 6 percent in the late 1970s. That development "jeopardizes our children’s future, making them vulnerable to chronic conditions such as diabetes and hypertension previously associated more with adults than with children," said Edward J. Sondik, director of the Center for Disease Control’s National Center for Health Statistics. The report said Mexican-American boys were at the highest risk, with 27 percent overweight followed by non-Hispanic girls at 23 percent. The child obesity issue is a major cause for concern, a health expert said to reporters."This is a trend that’s been at work since 1980 ... and as a trend, it shows no sign of reversing," the expert said. Child poverty also grew, reaching 11. 6 million in 2002, compared with 11. 2 million a year earlier. Children living with single females continued to experience a higher poverty rate in 2002 than their counterparts in married-couple families -- 40 percent compared with 9 percent. In 2002, 73 million children under 18 lived in the United States and made up 25 percent of the population.

单项选择题