Filters








4,338 Hits in 4.8 sec

Incremental maintenance of recursive views using relational calculus/SQL

Guozhu Dong, Jianwen Su
2000 SIGMOD record  
For example, transitive closure of acyclic graphs, and of undirected graphs, can be maintained in relational calculus after both single edge insertions and deletions.  ...  Very often the desired views (e.g. the transitive closure) cannot be defined in the standard language of the underlying database system.  ...  [4] considered the maintenance of constrained transitive closure of graphs with weighted edges (or nodes) by conjunctive queries.  ... 
doi:10.1145/344788.344808 fatcat:skqbr5qkmzg55gla3fpbpy7h4u

Zapato: Automatic Theorem Proving for Predicate Abstraction Refinement [chapter]

Thomas Ball, Byron Cook, Shuvendu K. Lahiri, Lintao Zhang
2004 Lecture Notes in Computer Science  
In this paper we report on a fast, lightweight, and automatic theorem prover called Zapato which we have built specifically to solve the queries produced during the abstraction refinement process.  ...  Both Newton and Constrain can refine the abstraction if they can find any spurious transitions in the path that they are examining. Paths are often spurious for multiple reasons.  ...  This core reason is a subset of the original conjuncts and is found by visiting the leaves of the proof tree constructed by the FOL conjunct solver.  ... 
doi:10.1007/978-3-540-27813-9_36 fatcat:gpftnlzrjvgthagthn5aj2vt4a

Collaborative data-driven workflows

Serge Abiteboul, Victor Vianu
2013 Proceedings of the 32nd symposium on Principles of database systems - PODS '13  
Acknowledgement We wish to thank Val Tannen for useful discussions on the update propagation model of collaborative workflows, inspired by the Orchestra approach to data sharing.  ...  The closure ϕ * V of a conjunctive constraint ϕ on a subset V of it variables is the conjunction of all non-trivial atomic constraints implied by ϕ, whose variables are in V .  ...  We recall the notion of conjunctive query with safe negation (CQ ¬ query for short). A term is a variable or a constant.  ... 
doi:10.1145/2463664.2463672 dblp:conf/pods/AbiteboulV13 fatcat:xjmfgalp3jei5f5yf6jozd3hwm

Dynamic Graph Queries

Pablo Muñoz, Nils Vortmeier, Thomas Zeume, Marc Herbstritt
2016 International Conference on Database Theory  
Our focus is on maintaining regular path queries, and extensions thereof, by first-order formulas.  ...  In particular we are interested in path queries defined by non-regular languages and in extended conjunctive regular path queries (which allow to compare labels of paths based on word relations).  ...  In the following, our goal is to maintain the transitive closure of G using a dynamic program with first-order update formulas.  ... 
doi:10.4230/lipics.icdt.2016.14 dblp:conf/icdt/MunozVZ16 fatcat:f4owlmo3kzhjxcqozvg645e5ja

A Temporal extension of Prolog

Tomas Hrycej
1993 The Journal of Logic Programming  
An example inspired by K. Forbus's Qualitative Process Theory illustrates how qualitative simulation and related tasks can be formulated in Temporal Prolog in a transparent and declarative way. a  ...  This research has been supported in part by the Bundesminister fiir Forschung und Technologie, grant No. ITW 8506 C9 (TEX-B research project).  ...  If a relationship between two intervals is constrained, all consequences for relations between other intervals (i.e., a transitive closure) are calculated.  ... 
doi:10.1016/0743-1066(93)90016-a fatcat:zlarijlzbvg43hwctdiwipwena

ZStream

Yuan Mei, Samuel Madden
2009 Proceedings of the 35th SIGMOD international conference on Management of data - SIGMOD '09  
By carefully designing the underlying infrastructure and algorithms, ZStream is able to unify the evaluation of sequence, conjunction, disjunction, negation, and Kleene closure as variants of the join  ...  Besides simple sequential patterns, ZStream is also able to detect other patterns, including conjunction, disjunction, negation and Kleene closure.  ...  The expression T 2 5 constrains the number of successive Google events in the Kleene closure to 5; the aggregate function sum() is applied to the attribute volume of all the events in the closure.  ... 
doi:10.1145/1559845.1559867 dblp:conf/sigmod/MeiM09 fatcat:isassa2fmffjnn37vmieh4gsdq

Dynamic Graph Queries [article]

Pablo Muñoz and Nils Vortmeier and Thomas Zeume
2015 arXiv   pre-print
Our focus is on maintaining regular path queries, and extensions thereof, by first-order formulas.  ...  In particular we are interested in path queries defined by non-regular languages and in extended conjunctive regular path queries (which allow to compare labels of paths based on word relations).  ...  In the following, our goal is to maintain the transitive closure of G using a dynamic program with first-order update formulas.  ... 
arXiv:1512.05511v1 fatcat:3utoxdfn5bhqjdta254yv6orri

Temporal Relationships in Databases

Surajit Chaudhuri
1988 Very Large Data Bases Conference  
The model provides a framework to estimate the cost of query evaluation and to identify domain characteristics for query optimization.  ...  We conclude by presenting an interesting computational model for the temporal domain that trades completeness of the deduction for computational efficiency. Some open problems are mentioned.  ...  This is a conjunctive query and can be decomposed into two primitive,queries. The answer to the query is 5'1 n SZ.  ... 
dblp:conf/vldb/Chaudhuri88 fatcat:xfbeln4evnccxcu5kql3jjl2oi

One Algorithm to Evaluate Them All: Unified Linear Algebra Based Approach to Evaluate Both Regular and Context-Free Path Queries [article]

Ekaterina Shemetova, Rustam Azimov, Egor Orachev, Ilya Epelbaum, Semyon Grigorev
2021 arXiv   pre-print
The Kronecker product-based algorithm for context-free path querying (CFPQ) was proposed by Orachev et al. (2020).  ...  Thus, we provide the alternative way to construct a slightly subcubic algorithm for CFPQ which is based on linear algebra and incremental transitive closure (a classic graph-theoretic problem), as opposed  ...  Let C 3 be a transitive closure matrix of the graph G with n vertices. We use an approach by Ibaraki and Katoh (1983) to maintain dynamic transitive closure.  ... 
arXiv:2103.14688v1 fatcat:fy73vloj5zcmjbbwis37rbexte

Learning transformation rules for semantic query optimization: a data-driven approach

S. Shekar, B. Hamidzadeh, A. Kohli, M. Coyle
1993 IEEE Transactions on Knowledge and Data Engineering  
This paper describes a framework and a closure algorithm to learning rules from a given data-distribution.  ...  Previous approaches to learning query transformation rules have been based on analyzing past queries.  ...  This research was supported by the graduate school of University of Minnesota, and the Minnesota Department of Transportation. Prof.  ... 
doi:10.1109/69.250077 fatcat:kf6s34rumrbq7da5a57ghnfqzy

Attribute-pair range rules [chapter]

Jerome Robinson, Barry G. T. Lowden
1998 Lecture Notes in Computer Science  
Metadata of this kind is useful in Semantic Query Optimisation and Remote Cache Management.  ...  The two predicates (antecedent and consequent) in each rule are Selection Conditions or constraints of the type found in database queries.  ...  It is therefore useful to know (as discussed in the next section) whether there is a limit to the amount of pre-processing to be done, since full transitive closure is a significant workload.  ... 
doi:10.1007/bfb0054524 fatcat:btoskl552bcrvayv7p4qe2jri4

Lecture Notes in Computer Science 1205

1999 Industrial robot  
Metadata of this kind is useful in Semantic Query Optimisation and Remote Cache Management.  ...  The two predicates (antecedent and consequent) in each rule are Selection Conditions or constraints of the type found in database queries.  ...  It is therefore useful to know (as discussed in the next section) whether there is a limit to the amount of pre-processing to be done, since full transitive closure is a significant workload.  ... 
doi:10.1108/ir.1999.04926fae.001 fatcat:jyfnaucg45g6lemwgg4cu4esqq

Physical design refinement

Nicolas Bruno, Surajit Chaudhuri
2007 ACM Transactions on Database Systems  
We first relax the expression above by removing the conjunct C.  ...  issue of how to transition between a given configuration and a new one.  ... 
doi:10.1145/1292609.1292618 fatcat:nze2z56qlngjnazjesaxxfch7q

Satisfiability algorithms for conjunctive queries over trees

James Cheney
2011 Proceedings of the 14th International Conference on Database Theory - ICDT '11  
We investigate the satisfiability problem for conjunctions of constraints over ordered, unranked trees, including child, descendant, following-sibling, root, leaf, and first/last child constraints.  ...  (v, w ) ∈ E + =⇒ (w, w ) ∈ E * } That is, the edges are those induced by the transitive closure of the edges of T , restricted to V .  ...  We can define abbreviations for their transitive closures: x + y ⇐⇒ x * y ∧ x ≈ y x + y ⇐⇒ x * y ∧ x ≈ y x ≺ y ⇐⇒ x y ∧ x ≈ y If we had taken the transitive closures as primitive, then defining their transitive  ... 
doi:10.1145/1938551.1938572 dblp:conf/icdt/Cheney11 fatcat:bv6lhu7tr5bmxgvhhpiiivhemi

Physical Design Refinement: The "Merge-Reduce" Approach [chapter]

Nicolas Bruno, Surajit Chaudhuri
2006 Lecture Notes in Computer Science  
We first relax the expression above by removing the conjunct C.  ...  Profiled workloads require slightly more overhead at runtime than inferred ones, · 17 since we need to analyze each query during optimization and maintain some counters as queries are executed.  ... 
doi:10.1007/11687238_25 fatcat:2zusihnzo5fkbgm5otcxhqwccy
« Previous Showing results 1 — 15 out of 4,338 results