Characterizations for functional dependency and Boyce-Codd normal form families
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چکیده
منابع مشابه
Characterizations for Functional Dependency and Boyce-CODD Normal Form Families
A functional dependency (fd) family was recently defined [20] as the set of all instances satisfying some set of functional dependencies. A Royce-Codd normal form, abbreviated RCNF. family is defined here as an fd-family specified by some RCNF set of functi!)nal dependem& . The purpose of this paper is to present set-theoretic/algebraic characterizations relating to both types of families. Two ...
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In the relational model of data the Boyce-Codd-Heath normal form, commonly just known as Boyce-Codd normal form, guarantees the elimination of data redundancy in terms of functional dependencies. For efficient means of data processing the industry standard SQL permits partial data and duplicate rows of data to occur in database systems. Consequently, the combined class of uniqueness constraints...
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In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: a r t i c l e i n f o a b s t r a c t The theory of functional dependencies is based on relations, i.e. sets of tuples. Over...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1983
ISSN: 0304-3975
DOI: 10.1016/0304-3975(83)90019-1