Kweelt: more than just “yet another framework to query XML!”
SIGMOD '01 Proceedings of the 2001 ACM SIGMOD international conference on Management of data
Database System Implementation
Database System Implementation
Rainbow: mapping-driven XQuery processing system
Proceedings of the 2002 ACM SIGMOD international conference on Management of data
Clock: Synchronizing Internal Relational Storage with External XML Documents
Eleventh International Workshop on Research Issues in Data Engineering on Document Management for Data Intensive Business and Scientific Applications
Agora: Living with XML and Relational
VLDB '00 Proceedings of the 26th International Conference on Very Large Data Bases
XPERANTO: Middleware for Publishing Object-Relational Data as XML Documents
VLDB '00 Proceedings of the 26th International Conference on Very Large Data Bases
An algebraic approach for incremental maintenance of materialized XQuery views
Proceedings of the 4th international workshop on Web information and data management
Rainbow: multi-XQuery optimization using materialized XML views
Proceedings of the 2003 ACM SIGMOD international conference on Management of data
Efficiently supporting order in XML query processing
WIDM '03 Proceedings of the 5th ACM international workshop on Web information and data management
Raindrop: a uniform and layered algebraic framework for XQueries on XML streams
CIKM '03 Proceedings of the twelfth international conference on Information and knowledge management
Tree logical classes for efficient evaluation of XQuery
SIGMOD '04 Proceedings of the 2004 ACM SIGMOD international conference on Management of data
Native Xquery processing in oracle XMLDB
Proceedings of the 2005 ACM SIGMOD international conference on Management of data
Efficiently supporting order in XML query processing
Data & Knowledge Engineering - Special issue: WIDM 2003
Conquering the heterogeneity and evolutionary nature of XML using XML union views
DBA'06 Proceedings of the 24th IASTED international conference on Database and applications
Automaton meets algebra: a hybrid paradigm for XML stream processing
Data & Knowledge Engineering - Special issue: ER 2003
From tree patterns to generalized tree patterns: on efficient evaluation of XQuery
VLDB '03 Proceedings of the 29th international conference on Very large data bases - Volume 29
DUMAX: a dual mode algebra for XML queries
Proceedings of the 2nd international conference on Scalable information systems
SQL/XML Performance Analysis of Parent/Ancestor Queries
ICCSA '08 Proceedings of the international conference on Computational Science and Its Applications, Part II
Towards a physical XML independent XQuery/SQL/XML engine
Proceedings of the VLDB Endowment
Isolating order semantics in order-sensitive xquery-to-SQL translation
BNCOD'07 Proceedings of the 24th British national conference on Databases
Performance analysis of child/descendant queries in an XML-enabled database
ICCSA'07 Proceedings of the 2007 international conference on Computational science and its applications - Volume Part III
TraCX: transformation of compressed XML
BNCOD'11 Proceedings of the 28th British national conference on Advances in databases
Web and semantic web query languages: a survey
Proceedings of the First international conference on Reasoning Web
The importance of algebra for XML query processing
EDBT'06 Proceedings of the 2006 international conference on Current Trends in Database Technology
Efficiently processing XML queries over fragmented repositories with partix
EDBT'06 Proceedings of the 2006 international conference on Current Trends in Database Technology
Optimising XML---RDF data integration: a formal approach to improve XSPARQL efficiency
ESWC'12 Proceedings of the 9th international conference on The Semantic Web: research and applications
Processing global XQuery queries based on static query decomposition
ISPA'07 Proceedings of the 5th international conference on Parallel and Distributed Processing and Applications
Hi-index | 0.00 |
A lot of work is being done in the database community on mapping of XML data into and out of relational database systems, specifically, the query processing over such data using XQuery. We discuss our solution, the XML Algebra Tree (XAT), as part of our larger XML management system called Rainbow.Rainbow uses XQuery to describe the loading and extracting of XML data into relational systems and also for the execution of queries against pre-defined XML views of that stored data. The XML algebra tree of the query against those views is merged with the queries that define the views to form a larger tree. Because the XML formatting operators are interleaved with the computation operators, this XAT must then be optimized before being translated into one or more SQL statements that can be executed on the database. SQL translation is composed of computation pushdown and SQL generation.The computation pushdown splits the tree into the XML-specific and SQL-doable operators, which is then going to be converted into SQL statements. However, the XAT after computation pushdown may contain unreferenced columns or unused operators. Leaving these operators in the tree will create unnecessarily large SQL statements and will slow down the overall execution.Our main contributions to XML query processing, outlined in this paper, are threefold. One, we describe an algebra based on XATs for modeling XQuery expressions. Two, we propose rewriting rules to optimize XQueries by XAT operator cancel out. Lastly, we show a cutting algorithm to remove unreferenced columns and operators from the trees. We have fully implemented the techniques discussed in this paper in the Rainbow system. A preliminary experimental study compares the performance of execution before and after operator cancel out and cutting.