On the relational representation of complex specialization structures
نویسندگان
چکیده
The mapping of entity-relationship schemas (ER schema) that contain complex specialization structures into the relational model requires the use of specific strategies to avoid inconsistent states in the final relational database. In this paper, we show that for this mapping to be correct it is required to enforce a special kind of integrity constraint, the key pairing constraint (KPC). We present a mapping strategy that use simple inclusion dependencies to enforce KPC and show that, this strategy can be used to correctly map specialization structures that are more general than the simple specialization structures considered by previous strategies. 0 20(w) Published by Elsevier Science Ltd.
منابع مشابه
On the irreducibility of the complex specialization of the representation of the Hecke algebra of the complex reflection group $G_7$
We consider a 2-dimensional representation of the Hecke algebra $H(G_7, u)$, where $G_7$ is the complex reflection group and $u$ is the set of indeterminates $u = (x_1,x_2,y_1,y_2,y_3,z_1,z_2,z_3)$. After specializing the indetrminates to non zero complex numbers, we then determine a necessary and sufficient condition that guarantees the irreducibility of the complex specialization of the repre...
متن کاملOrganization of Gatekeeping and Mental Framework in the System of Representation and Hierarchical Relational Structures of the Modern Society
Critical discourse analysis as a type of social practice reveals how linguistic choices enable speakers to manipulate the realizations of agency and power in the representation of action.The present study examines the relationship between language and ideology and explores how such a relationship is represented in the analysis of spoken text and to show how declarative knowledge, beliefs, attit...
متن کاملA Comparative Analysis of Institutional Identities in a Corpus of English and Persian News Interviews
Institutional identity as a concept in CDA is a field of study that deals with the identities that individuals in institutions obtain, one that merits deep research attention. News interviews as institutional instances can be analyzed based on the impersonal structures because interviewees see themselves as part of the institution and they may not take responsibility when they encounter problem...
متن کاملRepresentation of IS-A relations
Generalization/specialization hierarchies (IS-A relations for short) are basic semantic constructs proposed in most information system conceptual models. At the other side of design methodologies, where standard DBMSs are used, and will still be used for several tears, there is no explicit representation of these IS-A relations. As a consequence, all the current methodologies include a step thr...
متن کاملAn Object Model for Engineering Design
Applications requiring sophisticated modeling techniques raise challenging issues to software designers. CAD/CAM and genetics are example of applications that call for powerful modeling techniques. Existing approaches seem limited in their ability to support their demands. Relational database systems for example support only simple tables. The need to enhance their capabilities led to non-norma...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Inf. Syst.
دوره 25 شماره
صفحات -
تاریخ انتشار 2000