I have a table that satisfies the following relations: R(A, B, C, D, E, F, G, H, I, J, K, L, M, N) {A, B, C} is the primary key.
I know how to calculate a minimal cover-- ensure each functional dependency only has one attribute on the RHS,
Let\'s say my database tracks bird sightings (Note: I\'m really scraping the bottom of the barrel for examples).
I an reading through some examples of normalization, however I have come across one that I do not understand.
Here are the relationships between 3 objects - A, B and C. A:B - 1:M A:C - 1:M B:C - M:M, with the restriction that they must share the same A instance.
What is meant by the lossless join property in a relation schema? Is it the ability to maintain the semantics of information/data during the decomposition 开发者_JS百科of relations whilst normalising?
We have enums, free-text, and referenced fields etc. in our DB. Each enum has its own translation, free-text could be in any language. We\'d like to do efficient large-scale free-text searching and e
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What is the best solution/practice for situation like this? I have a table, that can reference to multiple tables (objects)?
Given a database system which deals with Staff, Customers and Suppliers, all of which have multiple possible phone numbers, how would you go about storing these numbers in a nice normalised way? I hav
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