Algebraic Characterization of Optimal Complements of Database Views
نویسنده
چکیده
A complement to a database view Γ is a second view Γ ′ which provides the information necessary to reconstruct the entire state of the main schema. View complementation is central in situations in which a view is to be updated, since the complement Γ ′ embodies the information not contained in Γ . In general, Γ may have many complements. In this work, an approach to identifying and constructing optimal relational complements for a class of relational views is initiated. The approach is based upon simple ideas of unique decompositions within the context of the semilattice of views of the base schema.
منابع مشابه
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تاریخ انتشار 2011