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This sort of question is a fairly regular star on this forum. You essentially appear to be asking about implementing an EAV (Entity Attribute Value) system. Bill Karwin (a big hitter on this forum) has a hilarious image which cleverly shows why this model should normally be avoided. Karwin has written a book about SQL anti-patterns and devotes his first ...


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If the variants are identified by a variant code at the base of their sku, is the variant code always in the same place? If so, you can always group together with the base sku. However, you might want to look at product grouping. As an example, if your catalog of products is exercise products. And you have fitbits. The Fitbit flex can be sold with ...


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There is a technique called "shared primary key. You can read about it, and pick up examples over on Stackoverflow, by checking out the tag of that name.


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A graph database would be a good candidate. They specialise at retrieving interconnected data and navigating the relationships between objects. The ones I'm familiar with allow dynamic schema so different objects can have different values. Some allow classes of objects to be constructed so some consistency can be enforced. The links between objects are ...


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A tuple relational calculus expression should be written with the usual language of first order logic. In this case, for instance, you could write: { [e.Name, d.Name] | Ǝ e ∈ Employee, Ǝ d ∈ Department . e.Dept_no = d.No } (a part from minor variations on the notation used, like “:” instead of “.”). The idea is that you obtain the result of the query (a ...



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