Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory最新文献_第5页

Datalog with Negation and Monotonicity 具有否定性和单调性的数据

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.19

Bas Ketsman, Christoph E. Koch

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引用次数: 2

Random Sampling and Size Estimation Over Cyclic Joins 循环连接上的随机抽样和大小估计

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.7

Y. Chen, K. Yi

引用次数: 16

When Can Matrix Query Languages Discern Matrices? 矩阵查询语言何时能识别矩阵?

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.12

Floris Geerts

引用次数: 4

Towards Streaming Evaluation of Queries with Correlation in Complex Event Processing 复杂事件处理中关联查询的流计算研究

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.14

Alejandro Grez, Cristian Riveros

{"title":"Towards Streaming Evaluation of Queries with Correlation in Complex Event Processing","authors":"Alejandro Grez, Cristian Riveros","doi":"10.4230/LIPIcs.ICDT.2020.14","DOIUrl":"https://doi.org/10.4230/LIPIcs.ICDT.2020.14","url":null,"abstract":"Complex event processing (CEP) has gained a lot of attention for evaluating complex patterns over high-throughput data streams. Recently, new algorithms for the evaluation of CEP patterns have emerged with strong guarantees of efficiency, i.e. constant update-time per tuple and constant-delay enumeration. Unfortunately, these techniques are restricted for patterns with local filters, limiting the possibility of using joins for correlating the data of events that are far apart. In this paper, we embark on the search for efficient evaluation algorithms of CEP patterns with joins. We start by formalizing the so-called partition-by operator, a standard operator in data stream management systems to correlate contiguous events on streams. Although this operator is a restricted version of a join query, we show that partition-by (without iteration) is equally expressive as hierarchical queries, the biggest class of full conjunctive queries that can be evaluated with constant update-time and constant-delay enumeration over streams. To evaluate queries with partition-by we introduce an automata model, called chain complex event automata (chain-CEA), an extension of complex event automata that can compare data values by using equalities and disequalities. We show that this model admits determinization and is expressive enough to capture queries with partition-by. More importantly, we provide an algorithm with constant update time and constant delay enumeration for evaluating any query definable by chain-CEA, showing that all CEP queries with partition-by can be evaluated with these strong guarantees of efficiency. 2012 ACM Subject Classification Information systems → Data streams; Theory of computation → Database query processing and optimization (theory); Theory of computation → Formal languages and automata theory; Theory of computation → Automata extensions","PeriodicalId":90482,"journal":{"name":"Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89969179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

What Makes a Variant of Query Determinacy (Un)Decidable? (Invited Talk) 什么使查询确定性(非)可决定的变体?(邀请谈话)

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.2

J. Marcinkowski

{"title":"What Makes a Variant of Query Determinacy (Un)Decidable? (Invited Talk)","authors":"J. Marcinkowski","doi":"10.4230/LIPIcs.ICDT.2020.2","DOIUrl":"https://doi.org/10.4230/LIPIcs.ICDT.2020.2","url":null,"abstract":"This paper was written as the companion paper of the ICDT 2020 invited tutorial. Query determinacy is a broad topic, with literally hundreds of papers published since late 1980s. This paper is not going to be a “survey” but rather a personal perspective of a person somehow involved in the recent developments in the area. First I explain how, in the last 30+ years, the question of determinacy was formalized. There are many parameters here: obviously one needs to choose the query language of the available views and the query language of the query itself. But – surprisingly – there is also some choice regarding what the word “to compute” actually means in this context. Then I concentrate on certain variants of the decision problem of determinacy (for each choice of parameters there is one such problem) and explain how I understand the mechanisms rendering such variants of determinacy decidable or undecidable. This is on a rather informal level. No really new theorems are presented, but I show some improvements of existing theorems and also simplified proofs of some of the earlier results. 2012 ACM Subject Classification Theory of computation → Database theory","PeriodicalId":90482,"journal":{"name":"Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74675508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Facets of Probabilistic Databases (Invited Talk) 概率数据库的各个方面(特邀演讲)

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.1

B. Kimelfeld

引用次数: 2

A Family of Centrality Measures for Graph Data Based on Subgraphs 一组基于子图的图数据中心性测度

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.23

Cristian Riveros, J. Salas

{"title":"A Family of Centrality Measures for Graph Data Based on Subgraphs","authors":"Cristian Riveros, J. Salas","doi":"10.4230/LIPIcs.ICDT.2020.23","DOIUrl":"https://doi.org/10.4230/LIPIcs.ICDT.2020.23","url":null,"abstract":"We present the theoretical foundations of a new approach in centrality measures for graph data. The main principle of our approach is very simple: the more relevant subgraphs around a vertex, the more central it is in the network. We formalize the notion of “relevant subgraphs” by choosing a family of subgraphs that, give a graph G and a vertex v in G, it assigns a subset of connected subgraphs of G that contains v. Any of such families defines a measure of centrality by counting the number of subgraphs assigned to the vertex, i.e., a vertex will be more important for the network if it belongs to more subgraphs in the family. We show many examples of this approach and, in particular, we propose the all-subgraphs centrality, a centrality measure that takes every subgraph into account. We study fundamental properties over families of subgraphs that guarantee desirable properties over the corresponding centrality measure. Interestingly, all-subgraphs centrality satisfies all these properties, showing its robustness as a notion for centrality. Finally, we study the computational complexity of counting certain families of subgraphs and show a polynomial time algorithm to compute the all-subgraphs centrality for graphs with bounded tree width. 2012 ACM Subject Classification Mathematics of computing→ Graph theory; Information systems → Graph-based database models","PeriodicalId":90482,"journal":{"name":"Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91536805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Current Challenges in Graph Databases (Invited Talk) 图数据库当前面临的挑战(特邀演讲)

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.3

Juan L. Reutter

引用次数: 1

Containment of UC2RPQ: The Hard and Easy Cases 遏制UC2RPQ:困难和简单的情况

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.9

Diego Figueira

引用次数: 9

A Simple Parallel Algorithm for Natural Joins on Binary Relations 二元关系自然连接的一种简单并行算法

Database theory-- ICDT : International Conference ... proceedings. International Conference on Database Theory Pub Date : 2020-01-01 DOI: 10.4230/LIPIcs.ICDT.2020.25

Yufei Tao

引用次数: 8