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Pemrograman Sistem Basis Data. Chapter III Data Model. In This Chapter You Will Learn. Pentingnya Model Data Abstraction Data Model Perkembangan Model Data. Pentingnya Data Model ???. Follows Business Rules Communication Tools (Designer, Programmer, End user)
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PemrogramanSistem Basis Data Chapter III Data Model
In This Chapter You Will Learn • Pentingnya Model Data • Abstraction Data Model • Perkembangan Model Data
Pentingnya Data Model ??? • Follows Business Rules • Communication Tools (Designer, Programmer, End user) • End-users have different views and needs for data
Contoh Business Rules • PT A menetapkansistempembayarandilakukandengantunaidankredit. Jikakitatidakpandaimenganalisamakamungkinsajadapatterjadiredudancy data yang menyebabkanterjadinyaanomali data. • DirjendPumempunyaiaplikasikeuangandenganmengikutiBaganStandarAkun yang ditetapkanMenKeu. Tiba2 gantimentridan BAS bergantimengikutiaturan yang barusehinggaterjadiPerubahansistemsecaramenyeluruh.
Important Business Rules • Membantuterciptanya Data Model yang akuratsesuaidengankebutuhanperusahaan. • Membantudesaignermengertikebiasaan, aturan, danlingkup data. • Membantudesaigneruntukmengertiprosesbisnisdariperusahaantersebut.
Abstraction Data Model A data model instance may be one of three kinds according to ANSI in 1970: • Conceptual Model • Internal Model • Eksternal Model
Conceptual Model Merupakansebuah Map darikonsepdanhubungannyasecaralebihrincimenjelaskantentang entity class danhubunganantar entity class tersebutbukandesain database. Contoh : Person mungkindapatmemilikisatu order ataulebih. Tetapi order hanyadapatdimilikisatu order.
Evolusi Model Data • Hierarchical • Network • Relational • Object Oriented
Hierarchical Data Model • A hierarchical data model is a data model in which the data is organized into a tree-like structure. The structure allows repeating information using parent/child relationships: each parent can have many children but each child only has one parent (also known as a 1:many ratio ).
Examples of Hierarchical Data Represented as Relational Tables • In this model, the employee data table represents the "parent" part of the hierarchy, while the computer table represents the "child" part of the hierarchy. As shown, each employee may possess several pieces of computer equipment, but each individual piece of computer equipment may have only one employee owner.
network model Where the hierarchical database model structures data as a tree of records, with each record having one parent record and many children, the network model allows each record to have multiple parent and child records, forming a generalized graph structure.
Object Oriented Data Model • Modeled both data and their relationships in a single structure known as an object • Basis of object oriented data model (OODM) • OODM becomes the basis for the object oriented database management system (OODBMS)