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A Survey of Research on Deductive Database Systems
 JOURNAL OF LOGIC PROGRAMMING
, 1993
"... The area of deductive databases has matured in recent years, and it now seems appropriate to re ect upon what has been achieved and what the future holds. In this paper, we provide an overview of the area and briefly describe a number of projects that have led to implemented systems. ..."
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Cited by 100 (6 self)
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The area of deductive databases has matured in recent years, and it now seems appropriate to re ect upon what has been achieved and what the future holds. In this paper, we provide an overview of the area and briefly describe a number of projects that have led to implemented systems.
On Expressing Stratified Datalog
, 1994
"... 1 Introduction Tiziana Catarci Isabel F. Cruz On Expressing Stratified Datalog catarci@infokit.dis.uniroma1.it ifc@cs.brown.edu ongate x; y; z in x ; in y ; gate x; y; z : ongate x; y; z ongate a; b; x ; gate x; y; z ; ongate c; d; y : Dipartimento di Informatica e Sistemistica Universit`a di Rom ..."
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1 Introduction Tiziana Catarci Isabel F. Cruz On Expressing Stratified Datalog catarci@infokit.dis.uniroma1.it ifc@cs.brown.edu ongate x; y; z in x ; in y ; gate x; y; z : ongate x; y; z ongate a; b; x ; gate x; y; z ; ongate c; d; y : Dipartimento di Informatica e Sistemistica Universit`a di Roma "La Sapienza" Via Salaria 113, I00198 Roma, Italy Department of Computer Science Brown University Providence, RI 029121910, USA Research partially supported by EEC under the Esprit Project 6398 VENUS. Partial support given by ONR Contract N0001491J4052, ARPA Order 8225. These two classes are however incomparable (see for example [Kan90]). We consider the broad class of stratified Datalog queries (which includes both linear and nonlinear queries) and propose an extended closure operator that expresses such queries when added to the relational algebra. We show that there exists a canonical form for stratified Datalog queries, and that suitable hypergraphs can be used to express them. ...
Generating specialized rules and programs for demanddriven analysis
 In Proc. 12th Int’l Conf. on Algebraic Methodology and Software Technology AMAST’08, volume 5140 of LNCS
, 2008
"... Abstract. Many complex analysis problems can be most clearly and easily specified as logic rules and queries, where rules specify how given facts can be combined to infer new facts, and queries select facts of interest to the analysis problem at hand. However, it has been extremely challenging to ob ..."
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Abstract. Many complex analysis problems can be most clearly and easily specified as logic rules and queries, where rules specify how given facts can be combined to infer new facts, and queries select facts of interest to the analysis problem at hand. However, it has been extremely challenging to obtain efficient implementations from logic rules and to understand their time and space complexities, especially for ondemand analysis driven by queries. This paper describes a powerful method for generating specialized rules and programs for demanddriven analysis from Datalog rules and queries, and further for providing time and space complexity guarantees. The method combines recursion conversion with specialization of rules and then uses a method for program generation and complexity calculation from rules. We compare carefully with the best prior methods by examining many variants of rules and queries for the same graph reachability problems, and show the application of our method in implementing graph query languages in general. 1
Evaluation of Regular Nonlinear Recursions by Deductive Database Techniques
, 1995
"... Nonlinear recursion is one of the most challenging classes of logic programs for efficient evaluation in logic programming systems. We identify one popular class of nonlinear recursion, regular nonlinear recursion, and investigate its efficient implementation by a deductive database approach. The a ..."
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Nonlinear recursion is one of the most challenging classes of logic programs for efficient evaluation in logic programming systems. We identify one popular class of nonlinear recursion, regular nonlinear recursion, and investigate its efficient implementation by a deductive database approach. The approach performs a detailed query binding analysis based on query information, constraint information and the structure of a recursion, selects an appropriate predicate evaluation order and generates an efficient query evaluation plan. Interesting query evaluation techniques, such as chainfollowing, chainsplit, and constraint pushing, are developed for the efficient evaluation of different kinds of queries. Furthermore, the technique can be extended to the evaluation of regular nonlinear recursions in HiLog and Flogic programs. The study not only presents a method for the evaluation of regular nonlinear recursions in a declarative way but also demonstrates the power of the deductive datab...
Linearizing some recursive logic programs
 IEEE Transactions on Knowledge and Data Engineering
, 1995
"... We give in this paper a sufficient condition under which the least fixpoint of the equation X = a + f(X)X equals the least fixpoint of the equation X = a + f(a)X. We then apply that condition to recursive logic programs containing chain rules: we translate it into a sufficient condition under which ..."
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Cited by 2 (0 self)
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We give in this paper a sufficient condition under which the least fixpoint of the equation X = a + f(X)X equals the least fixpoint of the equation X = a + f(a)X. We then apply that condition to recursive logic programs containing chain rules: we translate it into a sufficient condition under which a recursive logic program containing n ≥ 2 recursive calls in the bodies of the rules is equivalent to a linear program containing at most one recursive call in the bodies of the rules. We conclude with a discussion comparing our condition with the other approaches to linearization studied in the literature. 1 Introduction. We apply fixpoint techniques together with language theory tools to derive simple algorithms for answering some queries on recursive logic programs. We give sufficient conditions on the query and the logic program which enable us to find an iterative program, i.e. a program containing only rightlinear recursions,
Homomorphic Tree Embeddings and Their Applications to Recursive Program Optimization
, 1993
"... This paper is concerned with the problems of stage preserving linearization and 1boundedness for ..."
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This paper is concerned with the problems of stage preserving linearization and 1boundedness for
Parallelization of RightUniform Datalog Programs and of Chain Sirups
, 1994
"... A Datalog program is uniformly decomposable if we can create restricted versions of the original program, assign one version to a processor, and have each of them compute part of the output. The set of facts computed by all processors is the output of the program. A fact is computed in exactly on ..."
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A Datalog program is uniformly decomposable if we can create restricted versions of the original program, assign one version to a processor, and have each of them compute part of the output. The set of facts computed by all processors is the output of the program. A fact is computed in exactly one processor. The input consists of relations for both the extensional and intensional relations. We exhibit an interesting class of uniformly decomposable Datalog programs. A program in this class also has the property that we can partition it in This work was partially supported by NSF grants IRI9009902 and HRD9353271 759 such a way that each partition member can be evaluated by an arbitrary number of processors, with no communication or synchronization being required among them. Also, we consider an special case of the above class, namely, the set of binary chain sirups, and characterize them completely in terms of uniform decomposability. This set is bigger than the correspon...
A Visual Approach to Multilinear Recursion
"... . The problem of expressing complex queries in a friendly way is particularly relevant due to the growing diffusion of databases. However, the most significant proposals for extending the expressive power of the relational query languages are based on the logical paradigm. In particular, an extensi ..."
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. The problem of expressing complex queries in a friendly way is particularly relevant due to the growing diffusion of databases. However, the most significant proposals for extending the expressive power of the relational query languages are based on the logical paradigm. In particular, an extension of the Horn clause queries, i.e. the socalled stratified Datalog, yields stratified queries, that are a proper subset of fixpoint queries. It is a general opinion that logic is not a friendly interfacing medium for a casual user. As a consequence, other types of query languages, i.e. visual query languages, have been proposed, some of them having an expressive power higher than the relational algebra. Up to now, no visual query language has been proved to provide the expressive power of stratified Datalog. In this paper, we present QBD**, a visual query language, and show that it is able to express all stratified queries. 1 Introduction "One key question concerning query languages is wh...
Generalization of ZYTlinearizability for bilinear datalog programs JiHoon Kang, a,∗
, 2000
"... www.elsevier.com/locate/ic ..."