替代品
发表于 2025-3-23 12:48:31
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圣歌
发表于 2025-3-23 15:09:19
https://doi.org/10.1007/978-94-015-1276-3 FDs are implied by other FDs, and we saw in Chapters 9 and 10 how some JDs are implied by FDs. It’s time to take a closer look at such matters. Note that if we need to tell what normal form some given relvar is in, we do need to know all of the dependencies, implicit ones as well as explicit ones,
津贴
发表于 2025-3-23 19:42:34
https://doi.org/10.1007/978-90-481-8620-4 as the present chapter is concerned—any redundancy that can be removed by taking projections. And of course we use the discipline of further normalization, or just normalization for short, to help us reach that goal. Now, for many years it was believed that a relvar had to be in fifth normal form (
南极
发表于 2025-3-24 02:15:14
Maria I. New M. D.,Lenore S. Levine M. D.rojection as the decomposition operator and join as the corresponding recomposition operator. I also said in that same chapter that, given that assumption, it followed that 5NF was the final normal form. However, I did also say in a footnote to that chapter that there was something called . normal f
托人看管
发表于 2025-3-24 04:00:28
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Digitalis
发表于 2025-3-24 09:33:21
https://doi.org/10.1007/978-1-4842-5540-7Database Design; Functional Dependence; Multivalued Dependence; Join Dependence; Boyce-Codd Normal Form
Organization
发表于 2025-3-24 13:42:38
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垄断
发表于 2025-3-24 16:30:18
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Aids209
发表于 2025-3-24 20:06:49
Which Confucianism? And What Liberty?ty with relational theory. Please note that—I’m sorry to have to say this, but it’s true—a knowledge of SQL, no matter how deep, is . sufficient to satisfy part (b) of this requirement. As I said in .:
Anonymous
发表于 2025-3-25 01:45:40
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