An early version of the Z Standard included the deductive system W for reasoning about Z specifications. Later versions contain a different deductive system. In this paper we sketch a proof that W is relatively sound with respect to this new deductive system. We do this by demonstrating a semantic basis for a correspondence between the two systems, then showing that each of the inference rules ...

This paper highlights the limits of current implementations of SQL and shows how they can be overcome with deductive approaches. Deductive query languages subsuming relational ones must include constructors to allow users for submitting queries semantically equivalent to their relational counterparts. As deductive languages are based on first order predicate logic, they are able to capture rela...

This paper presents an experiment in the use of a deductive database system for computer network maintenance. There are relatively few practical applications of deductive databases. Takagi et.al. applied deductive databases to a practical problem. They utilized an indirect connectivity search capability of a deductive database system for a retrieval of complex con gurations in petrochemical pip...

The promise of rule-based computing was to allow end users to create, modify, and maintain applications without the need to engage programmers. But experience has shown that rule sets often interact in subtle ways, making them difficult to understand and reason about. This has impeded the wide-spread adoption of rule-based computing. This paper describes the design and implementation of XcelLog...

the concept of soft sets, introduced by molodtsov [20] is a mathematicaltool for dealing with uncertainties, that is free from the difficultiesthat have troubled the traditional theoretical approaches. in this paper, weapply the notion of the soft sets of molodtsov to the theory of hilbert algebras.the notion of soft hilbert (abysmal and deductive) algebras, soft subalgebras,soft abysms and sof...

We describe the MyYapDB, a deductive database system coupling the Yap Prolog compiler and the MySQL DBMS. We use our OPTYap extension of the Yap compiler, which is the first available system that can exploit parallelism from tabled logic programs. We describe the major features of the system, give a simplified description of the implementation and present a performance comparison of using stati...

This work describes a novel implementation of a deductive database system which fills some gaps other systems do not. In fact, this system was born to this end and since its inception, many new features have been added (null values, outer joins, aggregates, ...). In particular, it embodies both Datalog and SQL query languages, where the same database can be queried. It enjoys an actual interact...

The framework of algorithmic knowledge assumes that agents use algorithms to compute the facts they explicitly know. In many cases of interest, a deductive system, rather than a particular algorithm, captures the formal reasoning used by the agents to compute what they explicitly know. We introduce a logic for reasoning about both implicit and explicit knowledge with the latter defined with res...