Optimization of Relational Schemas Containing Inclusion Dependencies
نویسندگان
چکیده
A two-step optimization strategy for relational schemas that contains a class of inclusion dependencies is described. Both steps take into account additional information that indicates how to preserve each inclusion dependency in the presence of insertions an‘d deletioy. The first step eliminates inclusion dependencies which are redundant with respect to both the semantics of the data and the behavior of the transactions. The second step discards dependencies through a structural transformation that again preserves the semantics of the data and of the transactions and that applies both to ihrF and to iV# relational schemas.
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