Type derivation using the projection operation
We present techniques for deriving types from existing objectoriented types using the relational algebraic projection operation and for inferring the methods that are applicable to these types. Such type derivation occurs, for example, as a result of defining algebraic views over object types. We refactor the type hierarchy and place the derived types in the type hierarchy in such a way that the state and behavior of existing types remain exactly as before. Our results have applicability to relational databases extended with object-oriented type systems and to object-oriented systems that support algebraic operations.
KeywordsSource Type Accessor Method Surrogate Type Call Graph Projection Operation
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