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EDITOR'S FOREWORD

1999 Journal of computer and system sciences (Print)  
In addition to decidability results for conjunctive queries with linear constraints, they also consider a subclass of SQLlike queries for which better complexity bounds are obtained.  ...  Ibarra and Jianwen Su studies and presents new results on the containment and equivalence of queries with linear constraints.  ... 
doi:10.1006/jcss.1999.1640 fatcat:ecojxocqmzdb5erqiszngeo2zu

On the decidability of query containment under constraints

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini
1998 Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems - PODS '98  
For the case where q does not contain regular expressions, we provide a method for deciding query containment, and analyze its computational complexity.  ...  To the best of our knowledge, this yields the rst decidability result on containment of conjunctive queries with regular expressions.  ...  For the case where q does not contain regular expressions, we provide a method for query containment, thus showing that the problem is decidable, and analyze its computational complexity. 2.  ... 
doi:10.1145/275487.275504 dblp:conf/pods/CalvaneseGL98 fatcat:gii3q6zdtfheplwoo35zd5xot4

Positive higher-order queries

Michael Benedikt, Gabriele Puppis, Huy Vu
2010 Proceedings of the twenty-ninth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems of data - PODS '10  
We show that containment and equivalence are decidable when query variables are restricted to positive relational algebra and we identify the precise complexity of the problem.  ...  Query functionals are said to be equivalent if the output queries are equivalent, for each possible input query, and similarly for containment.  ...  We are very grateful to the anonymous referees of PODS for helpful comments and corrections. We thank TJ Green for suggestions and references that improved the camera-ready.  ... 
doi:10.1145/1807085.1807091 dblp:conf/pods/BenediktPV10 fatcat:eakqbexft5albml3sar5vzhezy

Query Answering over Description Logic Ontologies [chapter]

Diego Calvanese
2014 Lecture Notes in Computer Science  
The task of answering queries has been investigated intensively in the last years for a variety of DLs, and considering both data complexity, i.e., the complexity measured in the size of the extensional  ...  The associated results, accompanied by matching lower bounds, have contributed to shaping the computational complexity picture for ontology-based query answering.  ...  Intuitively, the canonical model for a DL-Lite ontology O = T , A contains the ABox A, and in addition might contain existentially implied objects, whose existence is enforced by the TBox assertions with  ... 
doi:10.1007/978-3-319-11558-0_1 fatcat:pftzblg5nbdqzbyif5yw6aimma

Complexity of Arithmetic in Warded Datalog+- [article]

Lucas Berent, Markus Nissl, Emanuel Sallinger
2022 arXiv   pre-print
Furthermore, we present an efficient reasoning algorithm for our newly defined language and prove descriptive complexity results for a recently introduced Datalog fragment with integer arithmetic, thereby  ...  Moreover, despite the significance of arithmetic for common data analytic scenarios, no decidable fragment of any Datalog+- language extended with arithmetic has been identified.  ...  For a Warded Bound Datalog Z program P and a fact α, deciding whether P |= α is P-complete in data complexity.  ... 
arXiv:2202.05086v1 fatcat:dnhm5jem2resri7mvrvrm7cssa

Finding Pairwise Intersections Inside a Query Range [article]

Mark de Berg, Joachim Gudmundsson, Ali D. Mehrabi
2015 arXiv   pre-print
and objects with small union complexity.  ...  We present data structures of size O(n( polylog n)) and with query time O((k+1)( polylog n)) time, where k is the number of reported pairs, for two classes of objects in the plane: axis-aligned rectangles  ...  In this section we obtain results for classes of constant-complexity objects (which may have curved boundaries) with small union complexity.  ... 
arXiv:1502.06079v1 fatcat:ldfsnpq7xzg5bnykgww4xhsfeu

The Impact of Disjunction on Reasoning under Existential Rules: Research Summary [article]

Michael Morak
2014 arXiv   pre-print
It is the precise objective of the doctoral thesis herein discussed, to investigate the impact on the complexity of query answering, of adding disjunction to well-known decidable Datalog+/- fragments,  ...  For sticky theories, the query answering problem becomes undecidable, even in the data complexity, and for weakly-acyclic query answering we see a reasonable and expected increase in complexity.  ...  In fact, for bounded (hyper)treewidth, the complexity table coincides with that of arbitrary queries.  ... 
arXiv:1405.5109v1 fatcat:4al4oxnkenb7pe3q64zqgtfet4

Stream Reasoning in Temporal Datalog [article]

Alessandro Ronca, Mark Kaminski, Bernardo Cuenca Grau, Boris Motik, Ian Horrocks
2018 arXiv   pre-print
language for stream reasoning applications).  ...  In this paper, we propose novel reasoning problems to deal with these challenges, and study their computational properties on Datalog extended with a temporal sort and the successor function (a core rule-based  ...  Acknowledgments This research was supported by the SIRIUS Centre for Scalable Data Access in the Oil and Gas Domain, the Royal Society, and the EPSRC projects DBOnto, MaSI 3 , and ED 3 .  ... 
arXiv:1711.04013v2 fatcat:mudpi2yksbcftgv4aiimpeojna

Equivalence of nested queries with mixed semantics

David DeHaan
2009 Proceedings of the twenty-eighth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '09  
We consider the problem of deciding query equivalence for a conjunctive language in which queries output complex objects composed from a mixture of nested, unordered collection types.  ...  The schema also contains a logical view defined by the following SQL query (we abbreviate relation names with capitals and use subscripts to distinguish repeated relations).  ...  Tompa for many helpful discussions during the course of this research, and to the anonymous reviewers for their thoughtful suggestions.  ... 
doi:10.1145/1559795.1559828 dblp:conf/pods/DeHaan09 fatcat:j23jeorzendx3mxl5s23mda3bi

Image query processing based on multi-level signatures

F. Rabitti, P. Savino
1991 Proceedings of the 14th annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '91  
The image query language addresses important aspects of the image interpretations resulting from image analysis, by defining partial conditions on the composition of the complex objects, requirements on  ...  The query is pre-processed on the signatures to jilter-out most of the images not sati~ing the query. Finally, an evaluation of the ejjiciency and precision of the signature technique is given.  ...  In this case, the images contain a finite set of objects with complex relationships among them.  ... 
doi:10.1145/122860.122891 dblp:conf/sigir/Rabitti91 fatcat:qpjo72sf75aavdjniqoku4yfw4

Finding Pairwise Intersections Inside a Query Range [chapter]

Mark de Berg, Joachim Gudmundsson, Ali D. Mehrabi
2015 Lecture Notes in Computer Science  
and objects with small union complexity.  ...  We present data structures of size O(n polylog n) and with query time O((k + 1) polylog n) time, where k is the number of reported pairs, for two classes of objects in the plane: axis-aligned rectangles  ...  In this section we obtain results for classes of constant-complexity objects (which may have curved boundaries) with small union complexity.  ... 
doi:10.1007/978-3-319-21840-3_20 fatcat:oeoelpebqbfn7gtq7vdsfzjc2u

Multiple Entry Indexing and Double Indexing

Victor Teixeira de Almeida, Ralf Hartmut Guting, Christian Duntgen
2007 11th International Database Engineering and Applications Symposium (IDEAS 2007)  
Traditional indexing techniques are not well suited for complex data types such as spatial, spatio-temporal, and multimedia data types, where an instance is a composite of multiple components.  ...  In this paper we propose two indexing techniques that allow the parts of a composite object to be indexed separately, called multiple entry indexing and double indexing.  ...  Indexing mechanisms are crucial for efficient query processing coping with these complex data types.  ... 
doi:10.1109/ideas.2007.4318103 dblp:conf/ideas/AlmeidaGD07 fatcat:5zjij2th3ffntc3axegsljfuc4

Conjunctive Query Containment and Answering under Description Logics Constraints [article]

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini
2005 arXiv   pre-print
We provide a method for query containment under Description Logic constraints, thus showing that the problem is decidable, and analyze its computational complexity.  ...  In this paper, we deal with unions of conjunctive queries, and we address query containment and query answering under Description Logic constraints.  ...  Complexity of Query Containment We analyze now the computational complexity of our algorithm for query containment. 20 · Diego Calvanese et al. Theorem 3.8.  ... 
arXiv:cs/0507067v1 fatcat:q7sn62kerbccjcaanh6svb3ttm

Finding Pairwise Intersections Inside a Query Range

Mark de Berg, Joachim Gudmundsson, Ali D. Mehrabi
2017 Algorithmica  
and objects with small union complexity.  ...  We present data structures of size O ( n · polylog n ) and with query time O ( ( k + 1 ) · polylog n ) time, where k is the number of reported pairs, for two classes of objects in R 2 : axis-aligned rectangles  ...  Our contribution is to obtain similar results for a broader class of objects than those of [21] , namely axis-aligned rectangles and objects with small union complexity.  ... 
doi:10.1007/s00453-017-0384-3 pmid:30956379 pmcid:PMC6428404 fatcat:bxt5dpw7ozbvdbfgzdp457oobi

A storage and access architecture for efficient query processing in spatial database systems [chapter]

Thomas Brinkhoff, Holger Horn, Hans-Peter Kriegel, Ralf Schneider
1993 Lecture Notes in Computer Science  
Due to the high complexity of objects and queries and also due to extremely large data volumes, geographic database systems impose stringent requirements on their storage and access architecture with respect  ...  Additionally, we incorporate into our architecture a new ingredient, the scene organization, for efficiently supporting set-oriented access of large-area region queries.  ...  For example, bio-computing is an important field of application for 3D-spatial objects.  ... 
doi:10.1007/3-540-56869-7_20 fatcat:p2otzbxrb5b6hjvxsjmfehaxhm
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