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Appendix E Hierarchical Model customer name customer streef customer_city account number balance customer account access date access date access_date access date account_number balance customer name customer_street customer city account customer Figure E.10 Tree-structure diagram with many-to-many relationships. The resulting tree-structure diagram is illustrated in Figure E.8b. An instance corresponding to the described schema appears in Figure E.9.It shows that: Hayes has account A-102,which was last accessed on 10 June 2009. Johnson has two accounts:A-101,which was last accessed on 24 May 2009, and A-201,which was last accessed on 17 June 2009. Hayes Main Harrison Johnson Alma Palo Alto Smith North Rye 10June2009 24May2009 17June2009 21une2009 3 June 2009 A-102 400 A-101 500A-201900 A-201 900 A-215 700 (a) A-102400 A-101500 A-201900 A-215700 10June2009 24May2009 17June2009 21June2009 3 June 2009 Hayes Main Harrison Johnson Alma Palo Alto Johnson Alma Palo Alto Smith North Rye Smith North Rye (b) Figure E.11 Sample database corresponding to diagram of Figure E.108 Appendix E Hierarchical Model Figure E.10 Tree-structure diagram with many-to-many relationships. The resulting tree-structure diagram is illustrated in Figure E.8b. An instance corresponding to the described schema appears in Figure E.9. It shows that: • Hayes has account A-102, which was last accessed on 10 June 2009. • Johnson has two accounts: A-101, which was last accessed on 24 May 2009, and A-201, which was last accessed on 17 June 2009. Figure E.11 Sample database corresponding to diagram of Figure E.10
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