On completing tables to satisfy functional dependencies
نویسندگان
چکیده
منابع مشابه
Evolving Example Relations to Satisfy Functional Dependencies
Example and counterexample relations are important during the process of database design in order to guide the database designer towards specifying a correct set of integrity constraints; we assume that the constraints are speciied in terms of functional dependencies (FDs). We propose a stochastic algorithm which evolves an example relation that satisses a set of FDs from a random relation of a...
متن کاملFunctional Dependencies of Data Tables Over Domains with Similarity Relations
We study attribute dependencies in a setting of fuzzy logic. Our dependencies are described by formulas A ⇒ B where A and B are fuzzy sets of attributes. The meaning of A ⇒ B is that any two objects that have similar values on attributes from A have also similar values on attributes from B. Our approach generalizes classical functional dependencies from databases and also several approaches to ...
متن کاملDesign by Example for SQL Tables with Functional Dependencies
An Armstrong relation satisfies the functional dependencies (FD) implied by a given FD set and violates all other FDs. Therefore, they form an instance of the design-by-example methodology: the example relation exhibits precisely those FDs that the current design perceives as meaningful for the application domain. The existing framework of Armstrong relations only applies to total relations. We...
متن کاملComputing Supports of Conjunctive Queries on Relational Tables with Functional Dependencies
The problem of mining all frequent queries on a relational table is a problem known to be intractable even for conjunctive queries. In this article, we restrict our attention to conjunctive projection-selection queries and we assume that the table to be mined satisfies a set of functional dependencies. Under these assumptions, we define and characterize two pre-orderings with respect to which t...
متن کاملData Tables with Similarity Relations: Functional Dependencies, Complete Rules and Non-redundant Bases
We study rules A ⇒ B describing attribute dependencies in tables over domains with similarity relations. A ⇒ B reads “for any two table rows: similar values of attributes from A imply similar values of attributes from B”. The rules generalize ordinary functional dependencies in that they allow for processing of similarity of attribute values. Similarity is modeled by reflexive and symmetric fuz...
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: Theoretical Computer Science
سال: 1985
ISSN: 0304-3975
DOI: 10.1016/0304-3975(85)90145-8