问题 单项选择题

有如下两个关系,其中雇员信息表关系EMP的主键是雇员号,部门信息表关系DEPT的主键是部门号。若执行下面列出的操作,哪一项操作不能成功执行 [*]

A.从DEPT中删除部门号='03'的行

B.在DEPT中插入行('06','计划部','6号楼')

C.将DEPT中部门号='02'的部门号改为'10'

D.将DEPT中部门号='01'的地址改为,5号楼'

答案

参考答案:C

解析:按照交互方式分类.可以将电子商务分为消费类电子商务、企业类电子商务和平台类电子商务。

解答题
单项选择题

As people age and need more help with daily activities, such as bathing or taking medication, moving to a facility that provides some assistance, without sacrificing independence, may be an option. This type of environment, known as assisted living, has emerged in the past two decades as an increasingly available option for housing and long-term care. The growth of assisted living facilities has leveled off in recent years, however, as the economic downturn hampered new construction and occupancy rates.

In 2007, there were approximately 38 000 assisted living facilities nationwide, serving about 975000 residents. The overwhelming majority of assisted living residents in the United States are female, according to the National Center for Assisted Living. One of the most common types of facilities that provide assisted living are called continuing care retirement communities, which offer a stepwise approach to care, says Kerry Peck, an elder law attorney based in Chicago. "The concept is you age in place," meaning you never have to leave the grounds for housing, he says, "You buy an apartment or cottage, and then as your health declines, the facility agrees to provide continuing care. Some of the most successful centers have independent living, then assisted living, then a nursing home for acute care. "

But much like deciding whether a nursing home is necessary, the decision to move into an assisted living facility is not an easy one. So what factors should you consider when looking for a place to move to Mainly, you should think about what activities you or your loved one need help with. People residing in assisted living facilities may need assistance with any number of daily activities, such as bathing, dressing, using the bathroom, cooking or eating. About 87 percent of residents need help preparing meals, for example, and 81 percent need help with managing or taking their medications, reports the NCAL. Most residents come from living in private homes or apartments; fewer come from living with adult children or other family members, from nursing home facilities, retirement or independent living communities, or another assisted living or group home.

For some people, however, assisted living may not be an option, mostly for financial reasons. Assisted living facilities cost an average of $ 34 000 annually in 2009, compared to about $ 74 000 per year for a nursing home, according to research published in January in Health Affairs. How this expense is paid varies. Residents can buy into a facility by paying a large, upfront sum of money, followed by smaller monthly assessment fees. Or if the resident opts for a facility where he can rent instead, he would pay monthly for the cost of housing and care. The facilities are also mostly located in areas where home values are higher and people nearby have higher incomes.

The facilities are situated in places where ()

A. residents can buy into a facility by paying a lot of money

B.residents are rich and there are a lot of aged people

C. there are retirement and independent living communities

D. home values are higher and people have higher incomes