Simple Question About RDBMS Design - SQL - I Need Suggestion [message #421921] |
Fri, 11 September 2009 17:28 |
peace2009
Messages: 11 Registered: July 2009
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Junior Member |
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Hello,
http://img3.imageshack.us/img3/6989/53645000.jpg
Beside CustomerFamilyMembers entity you will see (0,6). This means a customer does not need to have a family in case a customer is single. However, in case a customer has a family, the family members can not exceed 6 members. If i did (1, 6), this means i'm enforcing every customer (or newly inserted) record in Customer to be associated at least with one CustomerFamilyMembers record which is not true in case of a single customer, so (0,6) is the appropriate degree of participation. If i understand it wrongly, let me know please.
Thanks
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