Verification and transformation of complex and uncertain conceptual schemas

In database environment it is necessary to represent complex and uncertain information at conceptual level and then transform the conceptual schema into the logical one for ultimate implementation. It is also important to verify the conceptual schema with respect to the constraints imposed on the schema definition. In this paper we primarily focus on the verification and transformation of the conceptual schema For the purpose of verification of the conceptual schema represented by the ExIFO data model (the extension of the IFO data model), we introduce a number of invariants. We also describe the transformation algorithm for mapping the conceptual specification into a logical database schema represented with the extended NF2 database model. The system that we describe in this paper is implemented and it can test whether the given ExIFO specification is valid and transforms the conceptual specification into the logical schema. The transformation algorithm is computationally efficient and preserves the knowledge represented with verified conceptual schema.


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A significant effort has been made in representing imprecise information in database models by using fuzzy set theory. However, the research directed toward access structures to handle fuzzy querying effectively is still at an immature stage. Fuzzy querying involves more complex processing than the ordinary querying does. Additionally, a larger number of tuples are possibly selected by fuzzy conditions in comparison to the crisp ones. It is obvious that the need for fast response time becomes very important...
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Schmidt, Klaus Verner (Institute of Electrical and Electronics Engineers (IEEE), 2013-09-01)
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The event calculus is a logic programming formalism for representing events and their effects especially in database applications. This paper proposes the event calculus as a logic-based methodology for the specification and execution of workflows. It is shown that the control flow graph of a workflow specification can be expressed as a set of logical formulas and the event calculus can be used to specify the role of a workflow manager through a set of rules for the execution dependencies of activities. The...
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Halıcı, Uğur (Association for Computing Machinery (ACM), 1987-01-09)
In this paper, a method for concurrency control in distributed DBMSs, called Permission Test Method is proposed. The PT method satisfies the basic requirements for concurrency control, that is, it executes the transactions in a serializable order, deadlocks do not appear and indefinite postponment is prevented by the method. In PT method, transactions, which are permitted to run, are not aborted unless a related site failure occurs. Furthermore, the complexity analysis indicates that the algorithm will work...
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Citation Formats
A. Yazıcı, “Verification and transformation of complex and uncertain conceptual schemas,” INTERNATIONAL JOURNAL OF UNCERTAINTY FUZZINESS AND KNOWLEDGE-BASED SYSTEMS, pp. 655–679, 1997, Accessed: 00, 2020. [Online]. Available: