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我已经为一项作业制作了错误图和规范化表格(包括规范化的所有步骤)。有人可以告诉我它是否正确，如果不正确，请告诉我我哪里出错了
谢谢
这是案例研究
The CabsOnDemand Case Study:
A private taxi company called CabsOnDemand was established in Kathmandu in 2002. Since then, the company has grown steadily and now has offices in most of the main cities of Nepal. However, the company is now so large that more and more administrative staff are being employed to cope with the ever-increasing amount of paperwork. Furthermore, the communication and sharing of information within the company is poor. The Director of the company, Sanjiv Udash feels that too many mistakes are being made and that the success of his company will be short-lived if he does not do something to remedy the situation. He knows that a database could help in part to solve the problem and has approached you and your team to help in creating a database application to support the running of CabsOnDemand.
The Director has provided the following brief description of how CabsOnDemand operates.
Each office has a Manager, several taxi owners, drivers and administrative (Regular) staff. The Manager is responsible for the day-to-day running of the office. An owner provides one or more taxis to CabsOnDemand and each taxi is allocated to number of drivers for use. The majority of owners are also drivers themselves. For each taxi details such as vehicle Registration Number, model, make, colour, capacity, currentMileage, DueDate for mortgage are recorded.
For each staff, Staff Number, National Insurance Number, Address, Date of Birth, First Name, Last Name, Salary, Sex are recorded.
Each office is identified by unique number, it's location details, telephone and fax numbers are recorded.
Office issues contracts for clients and should record details of the contracts. Each contract is identified unique contract number, date at which contract was signed, it's completion time, total charge for contract signing and maximum number of job allocated are recorded.
CabsOnDemand taxis are not available for hire by the public hailing a taxi in the street but must be requested by first phoning the company to attend a given address. This request is treated as job and each job has to be identified uniquely too also all the details such as pick-up date, location, time, drop-off location, used mileages and total chargeable amount should be recorded.
There are two kinds of clients, namely private and business. The business provided by private clients is on an ad-hoc basis. During the first booking each client is given unique identity and other his/her's other details such as address information, name, contact details are collected.
However, the business provided by business clients is more formal and involves agreeing a contract of work with the business. A contract stipulates the number of jobs that CabsOnDemand will undertake for a fixed fee hence, extra details such as client's business type, fax numbers are recorded too.
As described above, when a job comes into CabsOnDemand the name, phone number and contract number of the client is taken and then the pick-up date/time and pick-up/drop-off addresses are noted. Each job is allocated a unique jobID. The nearest driver to the pick-up address is called on His/Her mobile and the job details is informed.
When a job is completed the driver should note the mileage covered or used and the charge made (for private clients only). If a job is not complete, the reason for the failed job should be note.
The Director has provided some examples of typical queries that the database application for CabsOnDemand should be able to answer once implemented.
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