Algebraic aspects of attribute dependencies
نویسندگان
چکیده
We exhibit some new connections between structure of an information system and its corresponding semilattice of equivalence relations. In particular, we investigate dependency properties and introduce a partial ordering of information systems over a fixed object set U which reflects the sub–semilattice relation on the set of all equivalence relations on U.
منابع مشابه
Fine-grain Incremental Implementation of Algebraic Speciications Note: Partial Support Received from the European Communities under Esprit Project 2177 (generation of Interactive Programming Environments, Phase 2 -gipeii) and from the Netherlands Organization for Scientiic Research -nwo, Project Incremental Program Gen- Erators
In a previous paper we described how an incremental implementation can be derived from algebraic speciications belonging to the subclass of well-presented primitive recursive schemes. We combined term rewriting with techniques for storage and re-use from attribute grammars. Type check speciications typically belong to the class of primitive recursive schemes. The uniformity of algebraic speciic...
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