Second-order signature
Ralf Hartmut Güting · 1993
We propose a framework for the specification of extensible database systems.A particular goal is to implement a software component for parsing and rule-based optimization that can be used with widely varying data models and query languages as well as representation and query processing systems.The key idea is to use second-order signature (and algebra), a system of two coupled many-sorted signatures, where the top-level signature offers kinds and type constructors and the bottom-level signature provides polymorphic operations over the types defiied as terms of the top level.Hence the top level can be used to define a data or representation model and the bottom level to describe a query algebra or a query processing algebra.We show the applicability of this framework by examples drawn from relational modeling and query processing.