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Optimal Algorithms for Ranked Enumeration of Answers to Full Conjunctive Queries [article]

Nikolaos Tziavelis, Deepak Ajwani, Wolfgang Gatterbauer, Mirek Riedewald, Xiaofeng Yang
2020 arXiv   pre-print
For full conjunctive queries, including cyclic ones, our approach is optimal in terms of the time to return the top result and the delay between results.  ...  We study ranked enumeration of join-query results according to very general orders defined by selective dioids.  ...  We are grateful to Hung Q. Ngo for reading drafts of this paper and providing valuable feedback.  ... 
arXiv:1911.05582v3 fatcat:6o76icz54fhhtcduouv64udvvu

Beyond Equi-joins: Ranking, Enumeration and Factorization [article]

Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
2021 arXiv   pre-print
We study theta-joins in general and join predicates with conjunctions and disjunctions of inequalities in particular, focusing on ranked enumeration where the answers are returned incrementally in an order  ...  Our approach achieves strong time and space complexity properties: with n denoting the number of tuples in the database, we guarantee for acyclic full join queries with inequality conditions that for every  ...  We developed the first rankedenumeration techniques that achieve non-trivial worst-case guarantees for a large class of these joins: For small , returning the top-ranked join answers for full acyclic queries  ... 
arXiv:2101.12158v3 fatcat:hi6su4vlsbdq7cc2hd3mnquxam

Ranked Enumeration of Conjunctive Query Results [article]

Shaleen Deep, Paraschos Koutris
2021 arXiv   pre-print
We investigate the enumeration of top-k answers for conjunctive queries against relational databases according to a given ranking function.  ...  We introduce the notion of decomposable and compatible ranking functions in conjunction with query decomposition, a property that allows for partial aggregation of tuple scores in order to efficiently  ...  In this article, we study the algorithmic problem of enumerating the result of a Conjunctive Query (CQ, for short) against a relational database where the tuples must be output in order given by a ranking  ... 
arXiv:1902.02698v3 fatcat:3kl72emlvrbazjbelc6sp7zn34

Optimal Join Algorithms Meet Top-k [article]

Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
2020 Proceedings of the ACM SIGMOD International Conference on Management of Data   pre-print
We demonstrate that this line of research warrants renewed attention in the challenging context of ranked enumeration for general join queries.  ...  Second, we will cover recent, as well as some older, approaches that emerged at the intersection to support efficient ranked enumeration of join-query results.  ...  Besides, we argue that they are essential for the design of optimal ranked-enumeration algorithms over joins, including generalizations that go beyond natural and Boolean conjunctive queries.  ... 
doi:10.1145/3318464.3383132 pmid:33568888 pmcid:PMC7872590 arXiv:2005.00448v1 fatcat:fahzpuj56reornbc7tv5kuyz4m

Sharing work in keyword search over databases

Marie Jacob, Zachary Ives
2011 Proceedings of the 2011 international conference on Management of data - SIGMOD '11  
The ATC manages the flow of tuples among a multitude of pipelined operators, minimizing the work needed to return the top-k answers for all queries.  ...  It computes and executes a set of relational sub-queries whose results are combined to produce the k highest ranking answers.  ...  We also thank the reviewers for their helpful feedback.  ... 
doi:10.1145/1989323.1989384 dblp:conf/sigmod/JacobI11 fatcat:qumcfaqgjfdgjpwscpfjztzsmq

Approximate lifted inference with probabilistic databases

Wolfgang Gatterbauer, Dan Suciu
2015 Proceedings of the VLDB Endowment  
We give a detailed experimental evaluation of our approach and, in the process, provide a new way of thinking about the value of probabilistic methods over non-probabilistic methods for ranking query answers  ...  Importantly, this algorithm is a strict generalization of all known results of PTIME self-join-free conjunctive queries: A query is safe if and only if our algorithm returns one single plan.  ...  WG would also like to thank Manfred Hauswirth for a small comment in 2007 that was crucial for the development of the ideas in this paper.  ... 
doi:10.14778/2735479.2735494 fatcat:safh6aiiwfdlxpitp3bipdxg7y

Approximate Lifted Inference with Probabilistic Databases [article]

Wolfgang Gatterbauer, Dan Suciu
2014 arXiv   pre-print
We give a detailed experimental evaluation of our approach and, in the process, provide a new way of thinking about the value of probabilistic methods over non-probabilistic methods for ranking query answers  ...  Importantly, this algorithm is a strict generalization of all known results of PTIME self-join-free conjunctive queries: A query is safe if and only if our algorithm returns one single plan.  ...  WG would also like to thank Manfred Hauswirth for a small comment in 2007 that was crucial for the development of the ideas in this paper.  ... 
arXiv:1412.1069v1 fatcat:pqzm45dp5rh6njv5wrybpdj3xq

Ranked Enumeration of Join Queries with Projections [article]

Shaleen Deep, Xiao Hu, Paraschos Koutris
2022 arXiv   pre-print
Recent work has made considerable progress in identifying optimal algorithms for ranked enumeration of join queries that do not contain any projections.  ...  In this paper, we initiate the study of the problem of enumerating results in ranked order for queries with projections.  ...  We also thank Wim Martens for the reference [15] that motivates the study of star queries.  ... 
arXiv:2201.05566v1 fatcat:sn4l5orwmratjfd55zzv52qnqe

Tractable Orders for Direct Access to Ranked Answers of Conjunctive Queries [article]

Nofar Carmeli, Nikolaos Tziavelis, Wolfgang Gatterbauer, Benny Kimelfeld, Mirek Riedewald
2020 arXiv   pre-print
We study the question of when we can answer a Conjunctive Query (CQ) with an ordering over the answers by constructing a structure for direct (random) access to the sorted list of answers, without actually  ...  In the absence of answer ordering, such a construction has been devised for the task of enumerating query answers of free-connex acyclic CQs, so that the access time is logarithmic.  ...  Existing ranked-enumeration algorithms rely on priority queue structures that compare a minimal number of candidate answers to produce the ranked answers one-by-one in order.  ... 
arXiv:2012.11965v2 fatcat:pjkge6ep6rh63o4pd4pn76c27m

Embedding Logical Queries on Knowledge Graphs [article]

William L. Hamilton, Payal Bajaj, Marinka Zitnik, Dan Jurafsky, Jure Leskovec
2019 arXiv   pre-print
Here we introduce a framework to efficiently make predictions about conjunctive logical queries – a flexible but tractable subset of first-order logic – on incomplete knowledge graphs.  ...  For instance, given an incomplete biological knowledge graph, we might want to predict "em what drugs are likely to target proteins involved with both diseases X and Y?"  ...  Acknowledgements The authors thank Alex Ratner, Stephen Bach, and Michele Catasta for their helpful discussions and comments on early drafts.  ... 
arXiv:1806.01445v4 fatcat:s6qwg3sosrflnbqb372v45ha6e

Threshold Queries in Theory and in the Wild [article]

Angela Bonifati and Stefania Dumbrava and George Fletcher and Jan Hidders and Matthias Hofer and Wim Martens and Filip Murlak and Joshua Shinavier and Sławek Staworko and Dominik Tomaszuk
2021 arXiv   pre-print
Threshold queries are an important class of queries that only require computing or counting answers up to a specified threshold value.  ...  of a ranking function that orders the query results by importance.  ...  We thank Andrea Calì, Leonid Libkin, Victor Lee, Juan Sequeda, Bryon Jacob, and Michael Schmidt for their useful comments and early feedback.  ... 
arXiv:2106.15703v2 fatcat:cmhu3aaoffggbltngg326vchne

A Comparative Analysis on Contingence Structured Data Methodologies

Kavita K. Beldar, M. D. Gayakwad, Debnath Bhattacharyya, Tai-hoon Kim
2016 International Journal of Software Engineering and Its Applications  
This project implements method to overcome unsureness of identical records that tightly conceal the proper instances of input and gives effective results for identical record.  ...  Heterogeneous structured datas give rise to different kind of information caliber issues regarding real-world structured datas. Identical records also a one major issue.  ...  Author introduced a technique to make top-k exact answers for conjunctive queries.  ... 
doi:10.14257/ijseia.2016.10.5.02 fatcat:3sg6ppq5qvcnpjz4ektq4lp6r4

Dissociation and Propagation for Approximate Lifted Inference with Standard Relational Database Management Systems [article]

Wolfgang Gatterbauer, Dan Suciu
2016 arXiv   pre-print
We give a detailed experimental evaluation of our approach and, in the process, provide a new way of thinking about the value of probabilistic methods over non-probabilistic methods for ranking query answers  ...  Importantly, this algorithm is a strict generalization of all known PTIME self-join-free conjunctive queries: A query is in PTIME if and only if our algorithm returns one single plan.  ...  WG would also like to thank Manfred Hauswirth for a small comment in 2007 that was crucial for the development of the ideas in this paper.  ... 
arXiv:1310.6257v4 fatcat:ematfjcsdbavzd7siv3q2bikza

Answering (Unions of) Conjunctive Queries using Random Access and Random-Order Enumeration [article]

Nofar Carmeli, Shai Zeevi, Christoph Berkholz, Benny Kimelfeld, Nicole Schweikardt
2019 arXiv   pre-print
As data analytics becomes more crucial to digital systems, so grows the importance of characterizing the database queries that admit a more efficient evaluation.  ...  We consider the tractability yardstick of answer enumeration with a polylogarithmic delay after a linear-time preprocessing phase.  ...  of enumerating the query answers.  ... 
arXiv:1912.10704v1 fatcat:ivrnht63ivhi7iw4mrsf3s7mou

Answers Partitioning and Lazy Joins for Efficient Query Relaxation and Application to Similarity Search [chapter]

Sébastien Ferré
2018 Lecture Notes in Computer Science  
We introduce two algorithms, answers partitioning and lazy join, that together significantly improve the efficiency of query relaxation.  ...  Query relaxation has been studied as a way to find approximate answers when user queries are too specific or do not align well with the data schema.  ...  We have addressed the efficient computation of relaxed queries and approximate answers (i.e., similar nodes), and it remains to evaluate their exploitation for tasks such as classification, case-based  ... 
doi:10.1007/978-3-319-93417-4_14 fatcat:sivoaqnk5rcvje4upzpeb53vzu
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