问答题


阅读以下说明和表，回答问题1至问题3。
[说明]
图12-5中显示一张交通违章处罚通知书。每一个交通违章通知书有一个惟一的编号。交通违章通知书包含了收到处罚的违章者记录、涉及违章的机动车记录、违章记录、处罚记录以及经办警察记录等信息。所根据这张通知书所提供的信息回答下面问题。
[问题2]
将问题1中的E-R模型(图12-6)转换成4个关系数据模型，要求标注主码和外码。

【参考答案】

司机(驾照号，姓名，地址，邮编，电话) PK=驾照号 机动车(牌照号，型号，制造厂，生产日......

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