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Data Normalization (2) IS 240 Database Lecture #5 2010-02-08 M. E. Kabay, PhD, CISSP-ISSMP Assoc. Prof. Information autonomy School of Business & Management, Norwich University mailto:mkabay@norwich.edu V: 802.479.7937 1 right of starting time publication © 2010 Jerry Post. all in all rights reserved. fathert Panic! ? We are not acting to converse 66 slides in one session ? Much of straight start out throughs material leave alone serve as approval and review for your studies ? Opportunity to discuss principles and illustrate them with specific cases 2 Copyright © 2010 Jerry Post. in all rights reserved. Overview of Todays proceeding ? Continue discussion of normalization ? Work on examples to corroborateher ? of the essence(p) to get involve in class discussion ? mickle absorb / merge concepts nevertheless by using them ? D not t t memorize without understanding Do t try to i ith t d t di ?Waste of your time ? Do the homework exercises seriou sly ?They will ensure success ?Students from previous IS240 classes possess reported earnest experiences in genuine jobs praised for understanding principles that help design well databases 3 Copyright © 2010 Jerry Post. in all rights reserved. Boyce-Codd Normal Form (BCNF) ? conceal dependency Employee-Specialty(E#, Specialty, Manager) ? Example: ? Employee-Specialty(E#, Specialty, Manager) ? Is in 3NF now. Employee(E#, Manager) ? Business rules.

Manager(Manager, Specialty) ? Employee may have many specialties. ? E h specialty has many motorcoachs. on an individual basis i lt h ? Each film director has only one specialty. ? Employee has only one manager for each specialt y. ? worry is hidden relationship between m! anager and specialty. Employee(E#, Specialty, Manager) ? Need break out table for manager. ? But then we fag outt need to repeat specialty. ? In real life, probably convey the duplication (specialty listed in both tables). Manager(Manager, Specialty) 4 Copyright © 2010 Jerry Post. All rights reserved. Fourth Normal Form (Keys) EmployeeTasks(EID, Specialty, ToolID) ? Technically, if you keyed every...If you want to get a full essay, order it on our website: OrderEssay.net

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