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Query containment and rewriting using views for regular path queries under constraints

Gösta Grahne, Alex Thomo
2003 Proceedings of the twenty-second ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '03  
Based on the query containment under constraints, we reason about constrained rewritings -using views-of regular path queries.  ...  We give a constructive characterization for computing optimal constrained rewritings using views.  ...  QUERY REWRITING USING VIEWS UNDER CONSTRAINTS We will now reason about rewriting of regular path queries using views based on the query containment under constraints.  ... 
doi:10.1145/773153.773165 dblp:conf/pods/GrahneT03 fatcat:2t23wwjkfjdtvjqfrd6rplueuy

Finding Irredundant Contained Rewritings of Tree Pattern Queries Using Views [chapter]

Junhu Wang, Kewen Wang, Jiuyong Li
2009 Lecture Notes in Computer Science  
Given query Q and view V , it has been shown that a contained rewriting of Q using V can be obtained by finding a useful embedding of Q in V .  ...  Contained rewriting and maximal contained rewriting of tree pattern queries using views have been studied recently for the class of tree patterns involving /, //, and [].  ...  A contained rewriting (CR), or simply rewriting, of query Q using view V is a new query Q such that, when evaluated over the answers to the view, Q produces part or all of the correct answers to the original  ... 
doi:10.1007/978-3-642-00672-2_12 fatcat:whmq3iom7rcr7j53ieiv2o4thi

Independence of Containing Patterns Property and Its Application in Tree Pattern Query Rewriting Using Views

Junhu Wang, Jeffrey Xu Yu, Chengfei Liu
2008 World wide web (Bussum)  
Second, given a set S of views, we want to know under what conditions a subset S ′ of S is redundant in the sense that for any query Q, the contained rewritings of Q using the views in S ′ are contained  ...  in those using the views in S − S ′ .  ...  Given a set S of views, we want to know under what conditions a subset S ′ of S is redundant in the sense that for any query Q, the contained rewritings of Q using the views in S ′ are contained in those  ... 
doi:10.1007/s11280-008-0057-x fatcat:5krg5himhbddpdgcph57wslaaq

Minimizing View Sets without Losing Query-Answering Power [chapter]

Chen Li, Mayank Bawa, Jeffrey D. Ullman
2001 Lecture Notes in Computer Science  
using the views.  ...  The problem of answering queries using views has been studied extensively due to its relevance in a wide variety of data-management applications.  ...  De nition 9. maximally-contained r ewritings A maximally-contained rewriting P of a query Q using a view set V satis es the following conditions: 1 P is a nite union of conjunctive queries using only the  ... 
doi:10.1007/3-540-44503-x_7 fatcat:4aank65xprdrjcqnfjdut5y5oy

Approximate Rewriting of Queries Using Views [chapter]

Foto Afrati, Manik Chandrachud, Rada Chirkova, Prasenjit Mitra
2009 Lecture Notes in Computer Science  
We study approximate, that is contained and containing, rewritings of queries using views.  ...  For contained rewritings, we present a sound and complete algorithm for constructing, for CQAC queries and views, a maximally-contained rewriting (MCR) whose all CQAC disjuncts have up to a predetermined  ...  The reason is that pruned-MiCR does not consider shared variables across query subgoals (i.e., variables that occur in two or more subgoals of the query) while minimizing the MiCR, see [1] for the details  ... 
doi:10.1007/978-3-642-03973-7_13 fatcat:6lezk733cbfwljp4rgcqus57zq

Query rewriting using views in the presence of inclusion dependencies

Qingyuan Bai, Jun Hong, Michael F. McTear
2003 Proceedings of the fifth ACM international workshop on Web information and data management - WIDM '03  
Query rewriting using views is an essential issue in data integration.  ...  We prove that our extended algorithm can find the maximally-contained rewriting of a conjunctive query using a set of conjunctive views in the presence of inclusion dependencies.  ...  PRELIMINARIES 2.1 Query Containment and Answering Queries Using Views We consider the problem of answering conjunctive queries using views.  ... 
doi:10.1145/956728.956729 fatcat:2qgb2j2wabg65d7yzi53h5mpt4

Query rewriting using views in the presence of inclusion dependencies

Qingyuan Bai, Jun Hong, Michael F. McTear
2003 Proceedings of the fifth ACM international workshop on Web information and data management - WIDM '03  
Query rewriting using views is an essential issue in data integration.  ...  We prove that our extended algorithm can find the maximally-contained rewriting of a conjunctive query using a set of conjunctive views in the presence of inclusion dependencies.  ...  PRELIMINARIES 2.1 Query Containment and Answering Queries Using Views We consider the problem of answering conjunctive queries using views.  ... 
doi:10.1145/956699.956729 dblp:conf/widm/BaiHM03 fatcat:oalzaspl7jbtjkp3g6w6a6noju

Complete and Equivalent Query Rewriting Using Views [chapter]

Jianguo Lu, Minghao Li, John Mylopoulos, Kenneth Cheung
2009 Lecture Notes in Computer Science  
We also assume that no queries contain redundant subgoal, and that neither query nor view contains comparison predicates. We use Datalog to define all the queries and views in this paper.  ...  Definition Query Rewriting Using Views The problem of query rewriting using views, a.k.a. answering query using views, is about finding a method to retrieve the resulting tuples of a query from some  ...  Test Summary Number of view s th a t s u c c e s s t r a n s l a t e i n t o D a ta lo g : 5 Total Appendix C Demonstration of QrwGUI QrwGUI is GUI program to rewriting a single query using different  ... 
doi:10.1007/978-3-642-00672-2_64 fatcat:akhgz2qbnfbsldh7dwfoi5qc3u

Scalable Query Reformulation Using Views in the Presence of Functional Dependencies [chapter]

Qingyuan Bai, Jun Hong, Michael F. McTear
2003 Lecture Notes in Computer Science  
The problem of answering queries using views in data integration has recently received considerable attention.  ...  In this paper, we extend the bucket-based algorithms to handle query rewritings using views in the presence of functional dependencies.  ...  We first identify views that contain no subgoal of the query and then check whether these views can provide any useful information for the query.  ... 
doi:10.1007/978-3-540-45160-0_46 fatcat:udft5dr5yverbgyjtk6nfchh4q

Rewriting Queries Using Views [chapter]

Chen Li
2016 Encyclopedia of Database Systems  
Given a query Q on T , a query P is called a contained rewriting of query Q using V if P uses only the views in V, and P exp is contained in Q as queries.  ...  DEFINITION Given a query on a database schema and a set of views over the same schema, the problem of query rewriting is to find a way to answer the query using only the answers to the views.  ...  CROSS REFERENCES Answering queries using views, Query optimization, Data integration, Data warehousing, Query containment, Global-as-view (GAV), Local-as-views (LAV), Open-world assumption (OWA), Closedworld  ... 
doi:10.1007/978-1-4899-7993-3_1071-2 fatcat:6g63chlznzdlvdczu55iukqe5a

Valuating Queries for Data Trading in Modern Cities

Ruiming Tang, Huayu Wu, Xiuqiang He, Stephane Bressan
2015 2015 IEEE International Conference on Data Mining Workshop (ICDMW)  
In this paper, we discuss the definition of a pricing model in which views are priced and queries are valuated using views.  ...  We therefore adapt the MiniCon algorithm, which was designed to answer queries using views, to the task at hand.  ...  Example 2.2: Let us consider a query and two views.  ... 
doi:10.1109/icdmw.2015.11 dblp:conf/icdm/TangWHB15 fatcat:fvbnpn5anbgcnmz4oraink3fm4

A Bucket-Based Approach to Query Rewriting Using Views in the Presence of Inclusion Dependencies

Qingyuan Bai, Jun Hong, Michael F. McTear, Hui Wang
2006 Journal of research and practice in information technology  
Definition 2 (Maximally-contained rewriting) Q' is a maximally-contained rewriting of a query Q using the views V=V 1 ,...  ...  We use the rules in the Datalog query language to represent conjunctive queries and views as used in Ullman (1997) .  ... 
dblp:journals/acj/BaiHM006 fatcat:uqvpuqqrijbfrofv7ulnpoxbre

Generating efficient plans for queries using views

Foto N. Afrati, Chen Li, Jeffrey D. Ullman
2001 SIGMOD record  
We study the problem of generating e cient, equivalent rewritings using views to compute the answer to a query.  ...  is used.  ...  Lemma 3.3 All LMRs of a query using views that use only view tuples of the query include all CMRs of the query. 2 2 Proof: For any CMR P of a query Q, b y Lemma 3.2, there is a CMR P 0 that uses only view  ... 
doi:10.1145/376284.375705 fatcat:gnjfdzmho5esrpjtg4nx25loaa

Finding Equivalent Rewritings in the Presence of Arithmetic Comparisons [chapter]

Foto Afrati, Rada Chirkova, Manolis Gergatsoulis, Vassia Pavlaki
2006 Lecture Notes in Computer Science  
The problem of rewriting queries using views has received significant attention because of its applications in a wide variety of datamanagement problems.  ...  For select-project-join SQL (a.k.a. conjunctive) queries and views, there are efficient algorithms in the literature, which find equivalent and maximally contained rewritings.  ...  Given a query Q and a view set V , a query P is a contained rewriting of query Q using V if P uses only the views in V , and P exp Q. That is, P computes a partial answer to the query.  ... 
doi:10.1007/11687238_55 fatcat:lsatvegvhfakzpnvnz3ymqurri

Answering graph pattern queries using views

Wenfei Fan, Xin Wang, Yinghui Wu
2014 2014 IEEE 30th International Conference on Data Engineering  
We show that a graph pattern query can be answered using a set of views if and only if the query is contained in the views.  ...  Answering queries using views has proven an effective technique for querying relational and semistructured data.  ...  We also provide a quadratic-time algorithm for answering pattern queries using views. Pattern containment.  ... 
doi:10.1109/icde.2014.6816650 dblp:conf/icde/FanWW14 fatcat:em4hrxddhzeljgzqwjknqalnf4
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