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📁 开耐饥梅陇大学 网上教程 ssd7 exercise5答案。 绝对 正确。 满分的答案。
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Entities and their attributes in E-Commerce Project Description:


Entities and Attributes                         What Value                                        Details              
1. BookTitle:
                  ISBN                          single value                                  
                  Title                         single value
                  Author                        multi-value                                      {author1, author2, ...}
                  PubNum                        composite value                                  ("E"or"N", Number)
                  Edition                       single value
                  PubDate                       composite value                                  (Year,Month,Day)
                  Price                         single value                                         
                  Discount                      single value
                  Description                   single value
                  QuantityInStock               single value
                  CateNum                       composite value                                  ("L"or"S", Number)

2. CategoryContainCategory:
                  LCateNum                      composite value                                  (Type,Number)
                  SCateNum                      composite value                                  (Type,Number)

3. Category:
                  CateNum                       composite value                                  (Type,Number)
                  CateName                      single value

4. CreditCard:
                  CCNum                         single value                
                  CCExpDate                     composite value                                  (Year,Month,Day)
                  CCType                        single value
                  CusNum                        composite value                                  ("C", Number)

5. Customer:
                  CusNum                        composite value                                  ("C", Number)
                  Email                         composite value                                  (username,@,website name)
                  Name                          composite value                                  (Fname,MI,Lname)
                  Address                       composite value                                  (DoorNumber,Street,City,State,Country)
                  PCode                         composite value                                  (Zipcode,Blockcode)
                  PhoNum                        composite value                                  (Districtcode, Number)
                  Password                      single value

6. DeliveryAgency:
                  DANum                         composite value                                  ("D",Number)
                  DAName                        single value
                  DAPhoNum                      composite value                                  (Districtcode, Number)

7. OrderLine:
                  OrderNum                      composite value                                  (CusNum, Times)
                  ISBN                          single value
                  Quantity                      single value
                  
8. Order:
                  OrderNum                      composite value                                  (CusNum, Times)
                  CusNum                        composite value                                  ("C", Number)
                  Address                       composite value                                  (DoorNumber,Street,City,State,Country)
                  CCNum                         single value
                  ShipDate                      composite value                                  (Year,Month,Day)
                  PlacedDate                    composite value                                  (Year,Month,Day)
                  ShipType                      single value
                  TotalCost                     single value

9. Promotion:
                  ISBN                          single value
                  DueDate                       composite value                                  (Year,Month,Day)
10. Publisher:
                  PubNum                        composite value                                  ("E"or"N", Number)             
                  Name                          single value
                  Address                       composite value                                  (DoorNumber,Street,City,State,Country)

11. Shipping:
                  ShipNum                       composite value                                  (OrderNum,Times)
                  OrderNum                      composite value                                  (CusNum, Times)
                  ShipDate                      composite value                                  (Year,Month,Day)
                  DANum                         composite value                                  ("D",Number)

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