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E.2 Tree-Structure Diagrams 7 access date customer : account customer name customer street depositor account number customer city balance (a)E-R diagram customer name customer street customer_city customer access_date access date account number balance account (b)Tree structure diagram Figure E.8 E-R diagram and its corresponding tree-structure diagram. .customer date,a many-to-one link from access date record type to customer record type date account,a many-to-one link from account record type to access date record type Hayes Main Harrison Johnson Alma Palo Alto Turner Putnam Stamford 10June2009 24May2009 17June2009 10June2009 A-102 400 A-101 500 A-201 900 A-305 350 Figure E.9 Sample database corresponding to diagram of Figure E.8b.E.2 Tree-Structure Diagrams 7 Figure E.8 E-R diagram and its corresponding tree-structure diagram. • customer date, a many-to-one link from access daterecord type to customer record type • date account, a many-to-one link from account record type to access date record type Figure E.9 Sample database corresponding to diagram of Figure E.8b
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