================== DATABASE DESIGN PROBLEM. NOTE*: I have to help someone who is

Question

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DATABASE DESIGN PROBLEM.

NOTE*: I have to help someone who is not physically here finish his assignment, but I've never learned anything about database. Show me the right way please. Do you have to use SQL to solve this problem?Read carefully and full answers will be greatly rated. thanks.

The following attributes form a relation that includes information about individual computers, their vendors, software packages running on the computers, computer users, and user authorizations. Users are authorized to use a specific software package on a specific computer during a specific time frame (characterized with attributes UserAuthorization Starts and UserAuthorizationEnds and secured with UserAuthorizationPassword). Software is licensed to be used on specific computers (potentially multiple software packages at the same time) until an expiration time (SoftwareLicenceExpires) at a specific price. Computers are sold by vendors, and each vendor has a support person with an ID, name, and phone extension. Each individual computer has a specific purchase price. The attributes are as follows: ComputerSerialNbr, VendorlD, VendorName, VendorPhone, VendorSupportID, VendorSupportName, VendorSupportExtension, SoftwarelD, SoftwareName, SoftwareVendor, SoftwareLicenceExpires, SoftwareLicencePrice UserlD, UserName, UserAuthorizationStarts, UserAuthorizationEnds UserAuthorizationPassword, PurchasePrice Based on this information, a. Identify the functional dependencies between the attributes. b. Identify the reasons why this relation is not in 3NF. c. Present the attributes organized so that the resulting relations are in 3NF.

Explanation / Answer

a. Functional Dependencies

ComputerSerialNbr -> PurchasePrice

VendorID -> VendorName,VendorPhone

VendorSupportID -> VendorSupportName,VendorSupportExtension,

SoftwareID -> SoftwareName,SoftwareVendor,SoftwareLicenseExpires,SoftwareLicensePrice

UserID ->UserName,UserAuthorizationStarts,UserAuthorizationEnds,UserAuthorizationPassword

b.

The relation is not in 3NF as all the attributes are not fully functionally dependent on ComputerSerialNbr.There is redundancy which can lead to inconsistency .

c. Relations in 3NF

Computer(ComputerSerialNbr , PurchasePrice)

Vendor(VendorID , VendorName,VendorPhone)

VendorSupport(VendorSupportID , VendorSupportName,VendorSupportExtension)

Software(SoftwareID , SoftwareName,SoftwareVendor,SoftwareLicenseExpires,SoftwareLicensePrice)

User(UserID , UserName,UserAuthorizationStarts,UserAuthorizationEnds,UserAuthorizationPassword)

underlined are primary keys.

Sql is not needed as it is normalization problem.

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