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Algebraic Optimization of Relational Queries with Various Kinds of Preferences [chapter]

Radim Nedbal
SOFSEM 2008: Theory and Practice of Computer Science  
To make a relational query language with the preference operator useful for practical applications, formal foundation for algebraic optimization, applying heuristics like push preference, has to be provided  ...  Therefore the efficient integration of querying with preferences into standard database technology is an important issue.  ...  Algebraic Optimization As the PO extends RA, the optimization of queries with preferences can be realized as an extension of a classical relational query optimization.  ... 
doi:10.1007/978-3-540-77566-9_33 dblp:conf/sofsem/Nedbal08 fatcat:f6q367rwa5do5e5wykyakycxsq

Towards Preference-aware Relational Databases

Anastasios Arvanitis, Georgia Koutrika
2012 2012 IEEE 28th International Conference on Data Engineering  
We present a preference-aware relational data model that extends database tuples with preferences and an extended algebra that captures the essence of processing queries with preferences.  ...  Our query processing strategies push preference evaluation inside the query plan and leverage its algebraic properties for finer-grained query optimization.  ...  For example, parts of the query that are not explicitly related to preferences are executed leveraging the native query optimizer.  ... 
doi:10.1109/icde.2012.31 dblp:conf/icde/ArvanitisK12 fatcat:k6sxm62jkrgbdn2frxodmotiim

PAQO: Preference-aware query optimization for decentralized database systems

Nicholas L. Farnan, Adam J. Lee, Panos K. Chrysanthis, Ting Yu
2014 2014 IEEE 30th International Conference on Data Engineering  
Our Preference-Aware Query Optimizer (PAQO) upholds both strict requirements and partially ordered preferences that are issued alongside of the queries that it processes.  ...  A consequence of this model is that should a user ever want to specify some aspect of how their queries are evaluated (e.g., a preference to read data from a specific replica, or a requirement for all  ...  RELATED WORK Preference SQL Our support for preferred constraints closely mirrors that of [11] , [12] in both the use of partiallyordered preference structures, and the syntax of the SQL extensions  ... 
doi:10.1109/icde.2014.6816670 dblp:conf/icde/FarnanLCY14 fatcat:6f3qwnifwrb2lnjwdbrq4htrfe

PDMS: AN EFFECTIVE PREFERENCE COUPLED DATA MANAGEMENT AND RETRIEVAL SYSTEM

SHAILESH P. KHAPRE, M. S. SALEEM BASHA, SUJATHA POTHULA, P. DHAVACHELVAN
2017 Journal of Engineering Science and Technology  
Management System" has been developed and implemented with proposed query optimization Algorithm Group Bottom Up.  ...  This paper shows the method for incorporating preferences in traditional Data Management schemes and how queries can be remodelled for confident data extraction; in this paper a prototype "Preference Data  ...  Fig. 9 .Fig. 10 . 910 Query optimization in relation to the number of preferences. Total execution time compared with selectivity of preferences.  ... 
doaj:c9defa065f1b40e290f6bc150af57616 fatcat:bhqhp7pqv5czpazyuxwnbr6lii

PAQO

Nicholas L. Farnan, Adam J. Lee, Panos K. Chrysanthis, Ting Yu
2013 Proceedings of the VLDB Endowment  
portions of their queries.  ...  With this proposal, we aim to demonstrate PAQO, a version of PostgreSQL's query optimizer that we have modified to produce plans that respect constraints specified through PASQL while optimizing userspecified  ...  Second, to support the PREFERRING clause, we have modified PostgreSQL's dynamic programming approach to query optimization to maintain only the most highly preferred plans over the course of optimization  ... 
doi:10.14778/2536274.2536309 fatcat:jvef66sbsfa3rmk7tvnmnc3mju

Semantic Optimization Techniques for Preference Queries [article]

Jan Chomicki
2005 arXiv   pre-print
Preference queries are relational algebra or SQL queries that contain occurrences of the winnow operator ("find the most preferred tuples in a given relation").  ...  In the context of semantic optimization of preference queries, we identify two fundamental properties: containment of preference relations relative to integrity constraints and satisfaction of order axioms  ...  We study semantic optimization of preference queries. Semantic query optimization has been extensively studied for relational and deductive databases [6] .  ... 
arXiv:cs/0510036v1 fatcat:wgqm42i5cbatjdpdjw5vye5lai

Semantic optimization techniques for preference queries

Jan Chomicki
2007 Information Systems  
Preference queries are relational algebra or SQL queries that contain occurrences of the winnow operator (find the most preferred tuples in a given relation).  ...  In the context of semantic optimization of preference queries, we identify two fundamental properties: containment of preference relations relative to integrity constraints and satisfaction of order axioms  ...  We study semantic optimization of preference queries. Semantic query optimization has been extensively studied for relational and deductive databases [6] .  ... 
doi:10.1016/j.is.2006.05.002 fatcat:7dcfs4diyvdj5ibzo2wewkkd3q

Personalized DBMS: an Elephant in Disguise or a Chameleon?

Georgia Koutrika
2011 IEEE Data Engineering Bulletin  
In this paper, we explain the need towards personalized and preference-aware query answering in the context of databases and we discuss how it can be enabled.  ...  Our objective is to discuss the pros and cons of existing approaches and the challenges and opportunities towards a truly personalized preference-aware DBMS.  ...  The rank operator [16] is an extension to relational algebra that enables pipelining and hence optimizing top-n queries.  ... 
dblp:journals/debu/Koutrika11 fatcat:pmvgagvpyfhcniyueoq6wway5i

OLAP preferences

Stefano Rizzi
2007 Proceedings of the ACM tenth international workshop on Data warehousing and OLAP - DOLAP '07  
Expressing preferences when querying databases is a natural way to avoid empty results and information flooding, and in general to rank results so that the user may first see the data that better match  ...  In this paper we outline the main research issues to be faced in order to develop a system for handling user preferences on OLAP cubes.  ...  preference relation (e.g., [6, 7] ), and on the subclass of skyline queries, where the preference relation is expressed as a Pareto composition of total orders on numerical attributes (e.g., [1, 2]  ... 
doi:10.1145/1317331.1317350 dblp:conf/dolap/Rizzi07 fatcat:mfsci5kqu5gm3cj7pszjezxsyi

Semantic Optimization of Preference Queries [article]

Jan Chomicki
2004 arXiv   pre-print
We present here a number of semantic optimization techniques applicable to preference queries.  ...  In our approach, preference queries are relational algebra or SQL queries that contain occurrences of the winnow operator ("find the most preferred tuples in a given relation").  ...  We study semantic optimization of preference queries. Semantic query optimization has been extensively studied for relational and deductive databases [CGM90] .  ... 
arXiv:cs/0402003v1 fatcat:o4u5555655e2plkglh6chznj3i

Enabling intensional access control via preference-aware query optimization

Nicholas L. Farnan, Adam J. Lee, Panos K. Chrysanthis, Ting Yu
2013 Proceedings of the 18th ACM symposium on Access control models and technologies - SACMAT '13  
In this demonstration, we present a version of PostgreSQL's query optimizer that we have modified to produce plans that respect these constraints while optimizing user-specified SQL queries in terms of  ...  of query evaluation.  ...  From here, we show the effect of preferred constraints on the optimization process by optimizing Queries 3 and 4 from Section 3.1.  ... 
doi:10.1145/2462410.2462428 dblp:conf/sacmat/FarnanLCY13 fatcat:onn7nozjkfcfnaxt27lxdagzja

Logical Foundations of Preference Queries

Jan Chomicki
2011 IEEE Data Engineering Bulletin  
We show how such preferences can be embedded into relational query languages.  ...  By separating the preferences from the query, preferencespecific query evaluation and optimization techniques can be formulated and preference modification studied.  ...  Query optimization A major advantage of the logic-based approach to preference queries is that rewrite-based query optimization is done in a natural and clean way.  ... 
dblp:journals/debu/Chomicki11 fatcat:h6ux2dbyrzc4blcgdugv5m3x3e

Preference-Driven Querying of Inconsistent Relational Databases [chapter]

Slawomir Staworko, Jan Chomicki, Jerzy Marcinkowski
2006 Lecture Notes in Computer Science  
We axiomatize desirable properties of preferred repair families and propose different notions of repair optimality.  ...  These goals are achieved by augmenting the framework of consistent query answers through various notions of preferred repair.  ...  The input consists of the relation instance and the priority relation, while the database schema, the integrity constraints, and the query are assumed to be fixed.  ... 
doi:10.1007/11896548_26 fatcat:6qqpelwyxjaolp4fq77tfhm3v4

The Preference SQL System - An Overview

Werner Kießling, Markus Endres, Florian Wenzel
2011 IEEE Data Engineering Bulletin  
The preference query optimizer performs algebraic transformations of preference relational algebra as well as cost-based algorithm selection e.g. for efficient Pareto / skyline evaluation.  ...  Preference SQL is a declarative extension of standard SQL by strict partial order preferences, behaving like soft constraints under the BMO query model.  ...  Preference Query Optimization Being an extension of standard SQL, Preference SQL can inherit the accumulated vast query optimization knowhow from relational databases.  ... 
dblp:journals/debu/KiesslingEW11 fatcat:c7b72txtqjg7thnvou73oamuee

PrefDB

Anastasios Arvanitis, Georgia Koutrika
2012 Proceedings of the 2012 international conference on Management of Data - SIGMOD '12  
In this demonstration we present a preference-aware relational query answering system, termed PrefDB.  ...  The key novelty of PrefDB is the use of an extended relational data model and algebra that allow expressing different flavors of preferential queries.  ...  The query optimizer rewrites the input query plan into a more efficient one based on the algebraic properties of the prefer operator.  ... 
doi:10.1145/2213836.2213927 dblp:conf/sigmod/ArvanitisK12 fatcat:a67wyybxjjegljgaro4q4smuge
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