'Fld' diaporamas de présentation

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ICS 421 Spring 2010 Normal Forms

ICS 421 Spring 2010 Normal Forms. Asst. Prof. Lipyeow Lim Information & Computer Science Department University of Hawaii at Manoa. Two More Rules. Union If X ? Y and X ? Z , then X ? YZ Eg . FLD ? A and FLD ? T, then FLD ? AT Decomposition If X ? YZ , then X ? Y and X ? Z

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ICS 321 Fall 2011 Functional Dependencies

ICS 321 Fall 2011 Functional Dependencies. Asst. Prof. Lipyeow Lim Information & Computer Science Department University of Hawaii at Manoa. Example: Movies1. What are the keys for this relational ? What if you ignore the column starName ? Can starName be a key ?.

197 views • 12 slides