Well-Defined NRC Queries Can Be Typed
نویسندگان
چکیده
We study the expressive power of the static type system of the Nested Relational Calculus NRC and show that on so-called homogeneous input and output types, the NRC type system is expressively complete: every untyped but homogeneously well-defined NRC expression can be equivalently expressed by a well-typed expression. The NRC static type system hence does not limit the expressive power of the query writer. Dedicated to Peter Buneman.
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