From relational to deductive databases
نویسنده
چکیده
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 relational semantics, which involves negation. In addition to negation, as e.g. needed to express set difference, usual relational outer join statements and aggregate functions must be taken into account for such subsuming deductive languages. We base our presentation on the grounds of DES (Datalog Educational System), a deductive database system that integrates both deductive and relational database languages in a common inference engine and system.
منابع مشابه
Update Control in Deductive Object Bases1
Deductive object bases are a combination of both deductive and objectoriented databases. This dissertation investigates the problem of update control for such databases. The data model is defined as an extreme case of a deductive database with only one extensional predicate and a multitude of axioms defining the object-oriented abstraction concepts. The advantages are twofold: a distinct concep...
متن کاملA Parallel Algorithm for the Generalized Partially Instantiated Same Generation Query in Deductive Databases
The expressive power and intelligence of traditional database systems can be improved by recursion. Using recursion, relational database systems are extended into knowledge-base systems (deductive database systems). Linear recursion is the most frequently found type of recursion in deductive databases. Deductive databases queries are computationally intensive and lend themselves naturally to pa...
متن کاملQuery Interoperation Among Object-Oriented and Relational Databases
We develop an eecient algorithm for the translation of high-order object queries to rst-order relational queries. The translation utilizes a canonical deductive database as a uniform representation of object-oriented schema and data. Object queries are translated to the canonical deductive database in which they are partially evaluated and optimized, before being translated to relational querie...
متن کاملModeling Uncertainty in Deductive Databases
Information Source Tracking (IST) method has been developed recently for the modeling and manipulation of uncertain and inaccurate data in relational databases. In this paper we extend the IST method to deductive databases. We show that positive uncertain databases, i.e. IST-based deductive databases with only positive literals in the heads and the bodies of the rules, enjoy a least model/least...
متن کاملMyrtle: A Set-Oriented Meta-Interpreter Driven by a "Relational" Trace for Deductive Databases Debugging
Deductive databases manage large quantities of data and, in general, in a set-oriented way. The existing systems of explanation for deductive databases do not take these constraints into account. We propose a tracing technique which consists of integrating a "relational" trace and an instrumented meta-interpreter using substitution sets. The relational trace e ciently gives precise information ...
متن کاملParallel Algorithms for the Generalized Same Generation Query in Deductive Databases
The intelligence of traditional database systems can be improved by recursion. Using recursion, relational database systems are extended into knowledgebase systems (deductive database systems). Linear recursion is the most frequently found type of recursion in deductive databases. Deductive databases queries are computationally intensive and lend themselves naturally to parallelization to speed...
متن کامل