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A time bound on the materialization of some recursively defined views

Yannis E. Ioannidis
1986 Algorithmica  
A virtual relation (or view) can be defined with a recursive Horn clause that is a function of one or more base relations.  ...  In general, the number of times such a Horn clause must be applied in order to retrieve all the tuples in the virtual relation depends on the contents of the base relations of the definition.  ...  In general, the number of times a has to be applied to get the materialization of reachable is not known. It depends on the initial contents of edge (the graph) and reachable. EXAMPLE 2.  ... 
doi:10.1007/bf01840452 fatcat:poxhsv5j5fdcfbgvs46ggfhat4

A Materialized View for the Same Generation Query in Deductive Databases

Nabil Arman
2012 Computer and Information Science  
The simplicity of implementation of linear recursive rules, like same generation rules, is far from the difficulty and the cost of computing the results of queries based on these recursive rules.  ...  In this paper, we propose the use of materialized views to speed up the evaluation of these queries and explain how to maintain the materialized view if the underlying base relation is updated.  ...  This non-recursive rule is given by: sg(X,Y):-par(Z,X),par(Z,Y) A query on the predicate "sg" that is defined by the recursive and the exit rule is called a same generation query.  ... 
doi:10.5539/cis.v5n6p1 fatcat:w4gf7kjwzzb4jmgdifcjur5gpe

Page 662 of Mathematical Reviews Vol. 52, Issue 2 [page]

1976 Mathematical Reviews  
The present work can be viewed as one of many possible ways to define and investigate flow chart measures. ’ The author defines the complexity of a flow chart computation as the sum of the costs of each  ...  The authors derive some upper bounds for the evaluation time under certain conditions and conclude with some conjectures on sharper results. K. H. V. Booth (Thunder Bay, Ont.)  ... 

MINT Views: Materialized In-Network Top-k Views in Sensor Networks

Demetrios Zeinalipour-Yazti, Panayiotis Andreou, Panos K. Chrysanthis, George Samaras
2007 2007 International Conference on Mobile Data Management  
Thus, our approach focuses on a subset V ′ (⊆ V ) that unveils only the k highest-ranked answers at the sink for some user defined parameter k.  ...  A typical materialized view V maintains the complete results of a query Q in order to minimize the cost of future query executions.  ...  We formulate the problem of constructing a hierarchy of recursively defined top-k views. We solve this problem by introducing MINT Views.  ... 
doi:10.1109/mdm.2007.34 dblp:conf/mdm/Zeinalipour-YaztiACS07 fatcat:usnzbpsjn5b6toz4opiqv5wha4

An Overview of the Theory of Computational Complexity

J. Hartmanis, J. E. Hopcroft
1971 Journal of the ACM  
The paper concentrates on the study of computational complexity measures defined for all computable functions and makes no attempt to survey the whole field exhaustively nor to present the material in  ...  Rather it presents the basic concepts, results, and techniques of computational complexity from a new point of view from which the ideas are more easily understood and fit together as a coherent whole.  ...  There exists a recursive function t such that the set of functions computable on a one-tape Turing machine in the time bound t is exactly the set of primitiw recursive functions.  ... 
doi:10.1145/321650.321661 fatcat:x2tcoo43pne5fpcjm56mjiuqqm

Foreword

Thomas Schwentick, Dan Suciu
2008 Theory of Computing Systems  
In a nutshell, it is interested in the probabilities of facts expressed by a conjunctive query assuming the knowledge of a conjunctive view over the underlying database.  ...  The paper provides non-trivial upper and lower bounds on the internal memory needed to compute relational algebra queries.  ...  Axiomatizing the logical core of XPath 2.0 by Balder ten Cate and Maarten Marx defines a clean and meaningful abstraction, Core XPath 2.0, of the navigational part of the XML query language XPath 2.0.  ... 
doi:10.1007/s00224-008-9156-4 fatcat:224btzm5ynfu7ho6nuzq23327u

Foundations of Online Structure Theory II: The Operator Approach [article]

Rod Downey, Alexander Melnikov, Keng Meng Ng
2021 arXiv   pre-print
One of the key ideas is that online algorithms can be viewed as a sub-area of computable analysis. Conversely, we also get an enrichment of computable analysis from classical online algorithms.  ...  We suggest a unifying approach using operators where we allow the input to be a countable object of an arbitrary complexity.  ...  Define a primitive recursive time bound for Ψ by the rule t(x) = t 0 ( t 1 (x), . . . , t m (x) ) + i t i (x), which can be rewritten into a primitive recursive schema using the standard techniques.  ... 
arXiv:2007.07401v4 fatcat:abmc5m2g3zhq5f5gdjk37hvxmi

Theory of computing in computer science education

Patrick C. Fischer
1971 Proceedings of the November 16-18, 1971, fall joint computer conference on - AFIPS '71 (Fall)  
time or do not exceed a bound on those available at compile time.  ...  In order to, make room for this recent material, a few lectures worth of the most basic material, e.g., the notion of a formal grammar as a generator of a language and. some of the equivalent interpretations  ...  time or do not exceed a bound on those available at compile time.  ... 
doi:10.1145/1478873.1478986 dblp:conf/afips/Fischer72 fatcat:fklwxch6hbachlbnyuvksa4kiy

The LDL system prototype

D. Chimenti, R. Gamboa, R. Krishnamurthy, S. Naqvi, S. Tsur, C. Zaniolo
1990 IEEE Transactions on Knowledge and Data Engineering  
This paper contains a comprehensive overview of the system and contains a description of the LDL language and the compilation techniques employed to translate LDL queries into target queries on the stored  ...  The paper further contains a description of the architecture and runtime environment of the system and the optimization techniques employed in order to improve the performance and assure the safety of  ...  Acknowledgments The authors would like to recognize the contribution the following persons: Brijesh  ... 
doi:10.1109/69.50907 fatcat:7hdqgrvklzf4zb2lm6xkejdk4a

Secure Querying of Recursive XML Views: A Standard XPath-based Technique [article]

Houari Mahfoud, Abdessamad Imine
2011 arXiv   pre-print
This rewriting enables us to avoid the overhead of view materialization and maintenance. A major concern here is that query rewriting for recursive XML views is still an open problem.  ...  We investigate the extension of the downward class of XPath, composed only by child and descendant axes, with some axes and operators and we propose a general approach to rewrite queries under recursive  ...  Figure 9 (b) represents the hospital DTD view D v of a research institute studying inherited patterns of some diseases.  ... 
arXiv:1112.2605v1 fatcat:hms4nnvtovfp5pceblebqhmvxm

vSPARQL: A view definition language for the semantic web

Marianne Shaw, Landon T. Detwiler, Natalya Noy, James Brinkley, Dan Suciu
2011 Journal of Biomedical Informatics  
We evaluate the expressivity of our approach by defining views for practical use cases and comparing our view definition language to existing query languages.  ...  We present a general solution for RDF information set reuse inspired by database views.  ...  We thank Nicki Dell for feedback on the manuscript, and Onard Mejino, Dan Cook, and Max Neal for help in defining the views.  ... 
doi:10.1016/j.jbi.2010.08.008 pmid:20800106 pmcid:PMC3042057 fatcat:7anb7nvu25fr7ki5acp6pb2vii

Incremental query evaluation in a ring of databases

Christoph Koch
2010 Proceedings of the twenty-ninth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems of data - PODS '10  
The k-th delta of a polynomial query of degree k without nesting is purely a function of the update, not of the database.  ...  We construct a ring of databases and use it as the foundation of the design of a query calculus that allows to express powerful aggregate queries.  ...  A predecessor of the compilation algorithm of Figure 3 was developed jointly with Yanif Ahmad and is described in [3] .  ... 
doi:10.1145/1807085.1807100 dblp:conf/pods/Koch10 fatcat:mjcffx7z3zflbeigyt4sqb6ju4

Remarks on Recursion versus Diagonalization and Exponentially Difficult Problems

Michael Machtey, Paul Young
1981 Journal of computer and system sciences (Print)  
A method based on recursion and making no use of diagonalization is given for proving lower bounds on computational complexity.  ...  PREFACE Among the topics Michael Machtey was working on at the time of his death in 1979 were connections between recursion and diagonalization.  ...  Obviously, Y is a linearly bounded measure. We next define C, a closure of B, and C' a different closure of C, by for some x, then by (B) of the lemma either n E C' or o,(x) = r,(x), x.  ... 
doi:10.1016/0022-0000(81)90042-8 fatcat:mluqncs3lzcnheohb7iisegnmm

Optimizing Recursive Information Gathering Plans in EMERAC

Subbarao Kambhampati, Eric Lambrecht, Ullas Nambiar, Zaiqing Nie, Gnanaprakasam Senthil
2004 Journal of Intelligent Information Systems  
This problem differs significantly from the traditional database query optimization problem as sources on the Internet have a variety of access limitations and the execution cost in information gathering  ...  In contrast to previous work, our approach can handle recursive query plans that arise commonly in the presence of constrained sources.  ...  Finally, we define #(α) as the number of bound variables in α that are not %-annotated.  ... 
doi:10.1023/b:jiis.0000012467.66268.9e fatcat:yyfydqfmfjhchcyftelmkghfea

Secure querying of recursive XML views

Houari Mahfoud, Abdessamad Imine
2012 Proceedings of the 21st international conference companion on World Wide Web - WWW '12 Companion  
This rewriting enables us to avoid the overhead of view materialization and maintenance. A major concern here is that query rewriting for recursive XML views is still an open problem.  ...  We investigate the extension of the downward class of XPath, composed only by child and descendant axes, with some axes and operators and we propose a general approach to rewrite queries under recursive  ...  Figure 9 (b) represents the hospital DTD view D v of a research institute studying inherited patterns of some diseases.  ... 
doi:10.1145/2187980.2188134 dblp:conf/www/MahfoudI12 fatcat:mgzf2xwgh5e7fmi456nb5kuyny
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