ER modelling from first relational principles
نویسندگان
چکیده
Entity-Relationship modelling is a popular technique for data modelling. Despite its popularity and wide spread use, it lacks a firm semantic foundation. We propose a translation of an ER-model into relation algebra, suggesting that this kind of algebra does provide suitable mechanisms for establishing a formal semantics of Entity-Relationship modelling. The work reported on here deals first with the techniques necessary for the translation, thus constructing a static view of an ER-model in an abstract setting of what might be called logic without variables. We then undertake a detailed analysis of the insertion and deletion operations for an ER-model represented in terms of the relation calculus.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 311 شماره
صفحات -
تاریخ انتشار 2004