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Chapter 8: The Enhanced Entity-Relationship Entity-Relationship (EER) Model

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CHAPTER 8: THE ENHANCED ENTITY-RELATIONSHIP (EER) MODEL Answers to Selected Eerc!ses 8"#$ – 8"#$ – No solution provided.

8"#% 8"#% - Consider the BN! ER sche"a o# $i%ure &.' and suppose that it is necessary to *eep trac* o# di##erent types o# CC+,NT ( (/N01CCT /N01CCT C2EC!/N01CCT ...) and 3+N (CR13+N 2+ME13+N ...). uppose that it is also desira4le to *eep trac* o# each account5s TRNCT/+Ns (deposits 6ithdra6als chec*s ...) and each loan5s 7MENTs 7MENTs99 4oth o# these include the a"ount date ti"e ... Modi#y the BN! sche"a usin% ER and EER concepts o# specialiation and %eneraliation. tate any assu"ptions you "a*e a4out the additional re;uire"ents.  Answer:

8"#8 8"#8 - No solution provided. 8"#& 8"#& - /denti#y all the i"portant concepts represented in the li4rary data4ase case study descri4ed here. /n particular identi#y the a4straction o# classi#ication (entity types and relationship types) a%%re%ation identi#ication and specialiationateA the nu"4er o# hours spent on the 6or* ?2oursA and the type o# 6or* done ?or*codeA. e use a 6ea* entity type ?serviceA to represent airplane service 4ecause the airplane re%istration nu"4er is used to identi#y a service record. n o6ner is either a person or a corporation. 2ence 6e use a union type (cate%ory) ?o6nerA that is a su4set o# the union o# corporation ?CorporationA and person ?7ersonA entity types. Both pilots 7ilotA and e"ployees ?E"ployeeA are su4classes o# person. Each pilot has speci#ic attri4utes license nu"4er ?3ic1Nu"A and restrictions ?RestrA9 each e"ployee has speci#ic attri4utes salary ?alaryA and shi#t hi#tA. ll Copyright © 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley.

Chapter 8: The Enhanced Entity-Relationship (EER) Model

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person entities in the data4ase have data *ept on their social security nu"4er ?snA na"e ?Na"eA address ?ddressA and telephone nu"4er ?7honeA. $or corporation entities the data *ept includes na"e ?Na"eA address ?ddressA and telephone nu"4er ?7honeA. The data4ase also *eeps trac* o# the types o# planes each pilot is authoried to #ly ?$liesA and the types o# planes each e"ployee can do "aintenance 6or* on ?or*s1onA. ho6 ho6 the s"all airport EER sche"a o# $i%ure 8.' "ay 4e represented in ,M3 notation. (Note: e have not discussed ho6 to represent cate%ories (union types) in ,M3 so you do not have to "ap the cate%ories in this and the #ollo6in% ;uestion.)  Answer:

8"''  8"'* – No solutions provided.

8"'+ - >ra6 a ,M3 dia%ra" #or storin% a played %a"e o# chess in a data4ase. ou "ay loo* at http: