منابع مشابه
An Ameliorated Methodology for the Abstraction and Minimization of Functional Dependencies of legacy ‘C’ Program Elements
Information systems of many organizations are processed through system of interrelated „C‟ programs. In a „C‟ program each statement contains functional dependencies amongst the attributes. Sometimes these functional dependencies may redundant in different statements. The existing application programs used in the maintenance of the information system are lengthy, and because of the perennial ma...
متن کاملImprecise Functional Dependencies
IntroductIon Functional dependencies represent a fundamental concept in the design of a database since they are capable of capturing some semantics of the data strongly connected with the occurrence of redundancy in a database. The development of applications working on fuzzy and multimedia databases has required the extension of the functional dependency notion to these new types of data. Unfo...
متن کاملFunctional Dependencies between Variables
Itisa standard practice to de ne the truth conditionsfora rst-orderform ula with a quanti erin term sofassignm entsto individualvariables. For exam ple,letM be a m odeland s a function (assignm ent)which assignsto variableselem entsin thedom ain ofM .Then a formula 9x (x)istruein M undersi thereisan assignm entswhich di ersfrom satm ostin thevalue itassignsto x,such that (x)istrue on M unders. ...
متن کاملFunctional Dependencies for XML
In this paper we address the problem of how to extend the deenition of functional dependencies (FDs) in incomplete relations to XML documents. An incomplete relation is said to strongly satisfy a FD if every completion of the relation, obtained by replacing all null values by data values, satisses the FD in the ordinary sense. We propose a syntactic deenition of strong FD satisfaction in a XML ...
متن کاملFunctional Dependencies in Horn
This paper studies functional dependencies in Horn theories, both when the theory is represented by its clausal form and when it is de ned as the Horn envelope of a set of models. We provide polynomial algorithms for the recognition of whether a given functional dependency holds in a given Horn theory, as well as polynomial algorithms for the generation of some representative sets of functional...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: International Journal of Computer Applications
سال: 2011
ISSN: 0975-8887
DOI: 10.5120/2453-3311