Titlebook: ICDT ‘88; 2nd International Co Marc Gyssens,Jan Paredaens,Dirk Gucht Conference proceedings 1988 Springer-Verlag Berlin Heidelberg 1988 alg

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Essential

Nausea

On using conditional rotation operations to adaptively structure binary search trees,e to be arranged lexicographically using a binary search tree. If . is known ., it is well known [7] that an optimal binary search tree may be constructed using . and .. We consider the case when . is not known .. A new restructuring heuristic is introduced that requires three extra integer memory l

fetter

Champion

Two-way join optimization in partitioned database systems,tion network is capable of parallel transmission, which differentiates the response time measure from the total cost measure. However, we do not make the standard simplifying assumption that communications between different sites is uniform, which results in a nonlinear optimization formulation of t

anaerobic

Deciding whether a production rule is relational computable,sts of a condition part which is a relational calculus expression and of an action part which is a sequence of database updates. The main problem addressed in this paper is to determine whether a rule program can be computed as a relational algebra program, i.e., whether the initial semantics of the

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高度

Sedative

On the complexity of queries in the logical data model,d ., which is complexity with respect to the size of the expressions denoting the queries. Our investigation shows that while the operations of product and union are essentially first-order operations, the power set operation is inherently a higher-order operation and is exponentially expensive. We

Affirm

On domain independent disjunctive databases,e is one for which the set of correct answers to any domain independent query is independent of the domains of variables in the database statements. We prove that every allowed stratified disjunctive database is domain independent and that every domain independent disjunctive database has an equival