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Heuristic containment check of partial tree-pattern queries in the presence of index graphs

Dimitri Theodoratos, Stefanos Souldatos, Theodore Dalamagas, Pawel Placek, Timos Sellis
2006 Proceedings of the 15th ACM international conference on Information and knowledge management - CIKM '06  
To cope with the high complexity of PTPQ containment in the presence of index graphs, we study a family of heuristic approaches for PTPQ containment based on structural information extracted from the index  ...  We address the problem of PTPQ satisfiability and containment in the absence and in the presence of index graphs, and we provide necessary and sufficient conditions for each case.  ...  ) query containment in the presence of an index graph (Relative Containment -RC), (c) heuristic query containment in the presence of an index graph, where precedence relationships are extracted from the  ... 
doi:10.1145/1183614.1183679 dblp:conf/cikm/TheodoratosSDPS06 fatcat:pvfimvuwo5hjhmqieghgz3xeci

A heuristic approach for checking containment of generalized tree-pattern queries

Pawel Placek, Dimitri Theodoratos, Stefanos Souldatos, Theodore Dalamagas, Timos Sellis
2008 Proceeding of the 17th ACM conference on Information and knowledge mining - CIKM '08  
In this paper, we consider a query language which generalizes TPQs by allowing the partial specification of a tree pattern.  ...  Partial tree-pattern queries (PTPQs) constitute a large fragment of XPath that flexibly permits the specification of a broad range of queries from keyword queries without structure, to queries with partial  ...  Further, the focus of [29] was on heuristic approaches in the presence of indexes called dimension graphs.  ... 
doi:10.1145/1458082.1458155 dblp:conf/cikm/PlacekTSDS08 fatcat:uvktzyvtibh5hf4z7a2er2nvuy

Subjectively Interesting Connecting Trees [chapter]

Florian Adriaens, Jefrey Lijffijt, Tijl De Bie
2017 Lecture Notes in Computer Science  
A natural way to show how query nodes are related is in the form of a tree in the network that connects them.  ...  In this paper, we define and investigate the new problem of mining subjectively interesting trees connecting a set of query nodes in a network, i.e., trees that are highly surprising to the specific user  ...  We consider trees because they are easy to interpret. We refer to the presence of a tree as a pattern found in the network.  ... 
doi:10.1007/978-3-319-71246-8_4 fatcat:ympiri5iuzhuzl2b352b6uuxtm

Query optimization in the presence of limited access patterns

Daniela Florescu, Alon Levy, Ioana Manolescu, Dan Suciu
1999 SIGMOD record  
We consider the problem of query optimization in the presence of limitations on access patterns to the data (i.e., when one must provide values for one of the attributes of a relation in order to obtain  ...  We show that in the presence of limited access patterns we must search a space of annotated query plans, where the annotations describe the inputs that must be given to the plan.  ...  the set of bushy trees does contain a query execution.plan without Cartesian products.  ... 
doi:10.1145/304181.304210 fatcat:y66a2jp5czgljbprzbozkpt4va

Query optimization in the presence of limited access patterns

Daniela Florescu, Alon Levy, Ioana Manolescu, Dan Suciu
1999 Proceedings of the 1999 ACM SIGMOD international conference on Management of data - SIGMOD '99  
We consider the problem of query optimization in the presence of limitations on access patterns to the data (i.e., when one must provide values for one of the attributes of a relation in order to obtain  ...  We show that in the presence of limited access patterns we must search a space of annotated query plans, where the annotations describe the inputs that must be given to the plan.  ...  the set of bushy trees does contain a query execution.plan without Cartesian products.  ... 
doi:10.1145/304182.304210 dblp:conf/sigmod/FlorescuLMS99 fatcat:zp4rdcsn4jddthalwp6lm7aflu

WaterFowl, a Compact, Self-indexed RDF Store with Inference-enabled Dictionaries [article]

Olivier Curé and Guillaume Blin and Dominique Revuz and David Faye
2014 arXiv   pre-print
The architecture of our prototype, largely based on the use of succinct data structures, enables the representation of triples in a self-indexed, compact manner without requiring decompression at query  ...  In this paper, we present a novel approach -- called WaterFowl -- for the storage of RDF triples that addresses some key issues in the contexts of big data and the Semantic Web.  ...  Again, these heuristics have been adapted to reorder some access patterns which is a major source of optimizations for SPARQL queries containing many graph patterns.  ... 
arXiv:1401.5051v1 fatcat:6qljapjnabgcxbfiy6da3xrwoy

QSEAfor fuzzy subgraph querying of KEGG pathways

Thair Judeh, Tin Chi Nguyen, Dongxiao Zhu
2012 Proceedings of the ACM Conference on Bioinformatics, Computational Biology and Biomedicine - BCB '12  
This approach allows for a greater latitude in fuzzy matching by focusing on the overall hierarchies of queries and graphs.  ...  Since hierarchies are only inherent in directed acyclic graphs, we have also developed a robust heuristic to heuristically solve the minimum feedback arc set problem.  ...  In the second stage, TwigStack merges and joins the partial results to compute twig query results. TwigStack, in conjunction with modified B-trees, can match query twig patterns in sub-linear time.  ... 
doi:10.1145/2382936.2382997 dblp:conf/bcb/JudehNZ12 fatcat:djj4fuv7krepvek2poxxo2k2dq

Reasoning with patterns to effectively answer XML keyword queries

Cem Aksoy, Aggeliki Dimitriou, Dimitri Theodoratos
2015 The VLDB journal  
However, the imprecision of the keyword queries usually results in a very large number of results of which only a few are relevant to the query.  ...  They exploit the structural properties of the tree data in order to filter out irrelevant results.  ...  The candidate results of a keyword query on an XML tree can be defined as the minimum connecting trees (MCTs) in the XML tree that contain an instance of all the keywords.  ... 
doi:10.1007/s00778-015-0384-3 fatcat:kkv4dj6n6rc3xnwvctp7jdf5b4

On the Optimal Ordering of Maps, Selections, and Joins Under Factorization [chapter]

Thomas Neumann, Sven Helmer, Guido Moerkotte
2006 Lecture Notes in Computer Science  
We examine the problem of producing the optimal evaluation order for queries containing joins, selections, and maps.  ...  First, we show that ignoring factorization during optimization can lead to plans that are far off the best possible plan: the difference in cost between the best plan considering factorization and the  ...  heuristic of pushing down selections in the query plan.  ... 
doi:10.1007/11788911_10 fatcat:xaf5xbnk5fbczd7o2doosqv5hq

Index structures and algorithms for querying distributed RDF repositories

Heiner Stuckenschmidt, Richard Vdovjak, Geert-Jan Houben, Jeen Broekstra
2004 Proceedings of the 13th conference on World Wide Web - WWW '04  
We discuss the implications of our architecture and propose an index structure as well as algorithms for query processing and optimization in such a distributed context.  ...  A technical infrastructure for storing, querying and managing RDF data is a key element in the current semantic web development.  ...  Indices over such graph structures now describe paths in the graph based on a certain pattern normally provided by the schema.  ... 
doi:10.1145/988672.988758 dblp:conf/www/StuckenschmidtVHB04 fatcat:ehtrjjvoczfnjooclfsfqehku4

Towards distributed processing of RDF path queries

Heiner Stuckenschmidt, Richard Vdovjak, Jeen Broekstra, Geert Jan Houben
2005 International Journal of Web Engineering and Technology  
We discuss the implications of our architecture and propose an index structure as well as algorithms for query processing and optimisation in such a distributed context.  ...  A technical infrastructure for storing, querying and managing RDF data is a key element in the current semantic web development.  ...  Indices over such graph structures now describe paths in the graph based on a certain pattern normally provided by the schema.  ... 
doi:10.1504/ijwet.2005.008484 fatcat:c5nun2piebcrzda4bylrndxocm

Scalable Pattern Matching in Metadata Graphs via Constraint Checking [article]

Tahsin Reza, Hassan Halawa, Matei Ripeanu, Geoffrey Sanders, Roger Pearce
2020 arXiv   pre-print
Pattern matching is a fundamental tool for answering complex graph queries.  ...  We show that the proposed technique: (i) enables highly scalable pattern matching in labeled graphs, (ii) supports arbitrary patterns with 100% precision, (iii) always selects all vertices and edges that  ...  For duplicate/distinct label verification, there is also TDS path constraint checking. The substructure in question may contain a cycle or a tree.  ... 
arXiv:1912.08453v2 fatcat:jrf3hcy6bnbcff6z256yefjowu

Highly Heterogeneous XML Collections: How to Retrieve Precise Results? [chapter]

Ismael Sanz, Marco Mesiti, Giovanna Guerrini, Rafael Berlanga Llavori
2006 Lecture Notes in Computer Science  
By means of similarity measures and semantic inverted indices we present an approach for improving the precision of query answers without compromising performance.  ...  Highly heterogeneous XML collections are thematic collections exploiting different structures: the parent-child or ancestor-descendant relationships are not preserved and vocabulary discrepancies in the  ...  Pattern Index. Given a pattern P , for every node v in P , all occurrences of nodes u in the target tree such that label(v) ≃ label(u) are retrieved, and organized level by level in a pattern index.  ... 
doi:10.1007/11766254_20 fatcat:so57d4nfejfcjh7jidg3qifgby

Towards Exploiting Query History for Adaptive Ontology-Based Visual Query Formulation [chapter]

Ahmet Soylu, Martin Giese, Ernesto Jimenez-Ruiz, Evgeny Kharlamov, Dmitriy Zheleznyakov, Ian Horrocks
2014 Communications in Computer and Information Science  
Therefore, in this paper, we propose a method using the log of past queries for ranking and suggesting query extensions as a user types a query, and identify emerging issues to be addressed.  ...  Ontology-based visual query systems employ ontologies and visual representations to depict the domain of interest and queries, and are promising to enable end users without any technical background to  ...  This research is funded by the FP7 of the European Commission under Grant Agreement 318338, "Optique".  ... 
doi:10.1007/978-3-319-13674-5_11 fatcat:rcqrr6khcbarnhhyu4fkhfk4ne

Mnemonic: A Parallel Subgraph Matching System for Streaming Graphs [article]

Bibek Bhattarai, Howie Huang
2022 arXiv   pre-print
Finding patterns in large highly connected datasets is critical for value discovery in business development and scientific research.  ...  This work focuses on the problem of subgraph matching on streaming graphs, which provides utility in a myriad of real-world applications ranging from social network analysis to cybersecurity.  ...  Those patterns are referred to as query graphs and each of their matches in the data graph are known as embeddings.  ... 
arXiv:2206.09983v1 fatcat:cc3exfcjjrbtdaworlf2dqmxxu
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