Schema Transformations as an Aid in View Integration

Two important problems in view integration are identifying and merging semantically equivalent but structurally different modelling constructs. One way to address this problem is to standardize the schemas to be integrated by applying a number of schema transformations to them. We formalize the notion of schema transformation in the context of a logic based modelling approach. We then introduce several transformations and show how they can be used in the view integration process.

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