Document (#10463)

Author
Staud, J.L.
Title
Datenbanken entwerfen mit dem ER-Modell
Issue
T.1-2.
Source
Datenbanken in Theorie und Praxis. 1995, H.1, S.9-16 (T.1), H. 2, S.24-30 (T.2)
Year
1995
Abstract
Datenbanken aufbauen - eine Aufgabe, der wir uns immer wieder gegenüber sehen, und sei es auch nur, um bestehende Datenbanken an die Veränderungen der dynamischen Welt anzupassen. Der erste Schritt beim Datenbankaufbau ist die Erstellung eines Datenmodells, genauer: eines konzeptionellen Datenmodells. Dieses stellt ein Abbild des zu betrachtenden Anwendungsbereichs dar (des Weltausschnitts) und wird mit einem Instrumentarium erstellt, das einerseits möglichst viel von den Strukturen, Abläufen, Regeln, usw. des Weltaussschnits erfaßt und das andererseits in ein 'physisches Modell' umgesetzt werden kann. Neben dem Relationalen Datenmodell ist der am meisten verbreitete Ansatz zur Modellierung von Weltausschnitten für Datenbanken der Entity- Relationship Ansatz. Die mit ihm erstellten Modelle werden ER-Modelle genannt. Einführung und Beispiele

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