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happynnc
Starting Member
7 Posts |
 Posted - 08/26/2012 : 23:08:45
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Hello everyone,
I am starting to study DB, and I read on the document that: "having two separate tables in a one-to-one relationship is considered bad practice."
But I have a requirement of designing of CUSTOMER as below:
- Customer have Membership Card ID
- Membership Card depends on Customer Type
So that I create 3 tables as below:
- Customer table (Customer_ID, Customer_FirstName, Customer_LastName, Customer_Address, Customer_City, Customer_Phone, Customer_Email, Membership Card) | Customer ID = PK
- Membership Card (MemberCard_ID, MemberCard_Type, MemberCard_IssueDate) | MemberCard_ID = PK
- Membership Type (MembershipType_ID, MembershipType_Description, MembershipType_Discount) | MembershipType_ID = PK
So, the Membership Type have 1-Many with Membership Card
And, Customer have 1-1 with Membership Card
In my mind, I think it ok, but because the lecture show that 1-1 is not good for DB design. How can I make my 3 table better design?
Thanks,
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1-1 relation
