Emmanuel Waller
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Emmanuel Waller has a total of 1 co-authors. Here are the top co-authors by number of shared publications:
- Jan Van Den Bussche
Limburgs Universitair Centrum Universitaire Campus 3590 Diepenbeek Belgium
1 shared publication
Latest Publications
- Open Access
Polymorphic type inference for the relational algebra
We give a polymorphic account of the relational algebra. We introduce a formalism of ``type formulas'' specifically tuned for relational algebra expressions, and present an algorithm that computes the ``principal'' type for a given expression. The principal type of an expression is a formula that specifies, in a clear and concise manner, all assignments of types (sets of attributes) to relation names, under which a given relational algebra expression is well-typed, as well as the output type that expression will have under each of these assignments. Topics discussed include complexity and polymorphic expressive power.
Open AccessPolymorphic type inference for the relational algebra
We give a polymorphic account of the relational algebra. We introduce a formalism of ``type formulas'' specifically tuned for relational algebra expressions, and present an algorithm that computes the ``principal'' type for a given expression. The principal type of an expression is a formula that specifies, in a clear and concise manner, all assignments of types (sets of attributes) to relation names, under which a given relational algebra expression is well-typed, as well as the output type that expression will have under each of these assignments. Topics discussed include complexity and polymorphic expressive power.