Chpt7 problems' solution

Chpt7 problems' solution - 13 There are many modification...

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13. There are many modification anomalies in the big expense report table. Insertion anomalies: Since ExpItemNo is the primary key, information about expense reports, expense categories, and users cannot be inserted unless there exists an expense item number. It should be possible to add expense reports, expense categories, and users independently of expense items. Update anomalies: Multiple rows will need to be changed when updating columns associated with expense reports, expense categories, and users. For example to update expense category limit, every expense item row in which it appears will need to be changed. Deletion anomalies: Deleting a row can inadvertently remove details about a user, expense report, or expense category. If the user, expense report, or expense category is used in only one expense item, the entity (user, expense report, or expense category) will be deleted. 14. The following FDs violate 2NF because they involve part of a key on the LHS. There
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This note was uploaded on 12/22/2009 for the course DBST DBST 651 taught by Professor Yelena - ta during the Spring '09 term at MD University College.

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Chpt7 problems' solution - 13 There are many modification...

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