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Performing grouping and aggregate functions in XML queries

Huayu Wu, Tok Wang Ling, Liang Xu, Zhifeng Bao
2009 Proceedings of the 18th international conference on World wide web - WWW '09  
In this paper, we extend our previous XML query processing algorithm, VERT, to efficiently perform grouping and aggregate function in queries.  ...  Given the explicit grouping operation in a query, how to efficiently compute grouping and aggregate functions over XML document is not well studied yet.  ...  operation and compute aggregate functions in XML queries with complex predicate.  ... 
doi:10.1145/1526709.1526844 dblp:conf/www/WuLXB09 fatcat:yas3xap72nemjcjsrcibr7fsaq

Group-by and Aggregate Functions in XML Keyword Search [chapter]

Thuy Ngoc Le, Zhifeng Bao, Tok Wang Ling, Gillian Dobbie
2014 Lecture Notes in Computer Science  
In this paper, we study how to support group-by and aggregate functions in XML keyword search.  ...  and relationships in order to guarantee the correctness of the results of aggregation functions; and (3) how to compute a keyword query with group-by and aggregate functions.  ...  -Designing the syntax for an XML keyword query with group-by and aggregate functions (Section 2).  ... 
doi:10.1007/978-3-319-10073-9_10 fatcat:k4crccrtnzcvnk4q63iiwiemki

A Landscape of XML Data from Analytics Perspective

Pratima Singh, Shelly Sachdeva
2020 Procedia Computer Science  
In this work, an attempt has been made to perform analytical functions using XQuery on an XML data and compare its performance with Analytical SQL queries in terms of execution time.  ...  In this work, an attempt has been made to perform analytical functions using XQuery on an XML data and compare its performance with Analytical SQL queries in terms of execution time.  ...  An experiment has been performed on openEHR health care data that is in XML format and proved that the performance of XML data is not always poor.  ... 
doi:10.1016/j.procs.2020.06.046 fatcat:34lz4gu2rjeuzfq3uvgqadnola

Database-Centric Programming for Wide-Area Sensor Systems [chapter]

Shimin Chen, Phillip B. Gibbons, Suman Nath
2005 Lecture Notes in Computer Science  
To demonstrate the effectiveness of X-Tree Programming in achieving these goals, we have incorporated the model into IrisNet, a shared infrastructure for wide-area sensing, and developed several widely  ...  , and efficient distributed execution.  ...  Other common computation paradigms include (1) computing multiple aggregates from the same set of data sources, and (2) performing a group-by query, i.e., grouping data into classes and computing the same  ... 
doi:10.1007/11502593_10 fatcat:67qiv34kwbetvkgfwj2kc3nwgu

Unifying the Processing of XML Streams and Relational Data Streams

Xin Zhou, H. Thakkar, C. Zaniolo
2006 22nd International Conference on Data Engineering (ICDE'06)  
Indeed, we show that YFilter, which is capable of efficiently processing multiple complex XML queries, can be easily integrated in Stream Mill via ESL user-defined and systemdefined aggregates.  ...  This enables a close cooperation of their query languages, resulting in great power and flexibility.  ...  Unfortunately, it lacks support for basic grouping functionalities which are normal in SQL, not to mention complex OLAP queries, and non-blocking queries on streaming data.  ... 
doi:10.1109/icde.2006.165 dblp:conf/icde/ZhouTZ06 fatcat:dmsmnms4hja73igh3rgfq33eqi

Towards practical meta-querying

Jan Van den Bussche, Stijn Vansummeren, Gottfried Vossen
2005 Information Systems  
Representing stored queries in XML, and using the standard XML manipulation language XSLT as a sublanguage, we show that just a few features need to be added to SQL to turn it into a fully-fledged meta-query  ...  We describe a meta-querying system for databases containing queries in addition to ordinary data. In the context of such databases, a meta-query is a query about queries.  ...  Acknowledgements We are indebted to Frank Neven and Dirk Van Gucht for inspiring conversations.  ... 
doi:10.1016/ fatcat:2z3fgfs2ardzvks7slhi7tmbca


Ying Guang Li, Stéphane Bressan, Gillian Dobbie, Zoé Lacroix, Mong Li Lee, Ullas Nambiar, Bimlesh Wadhwa
2001 Proceedings of the tenth international conference on Information and knowledge management - CIKM'01  
We illustrate its use by presenting and discussing the performance comparison against XOO7 of three different query processing platforms for XML.  ...  In this paper, with a focus on efficiency and concreteness, we propose a pragmatic first step toward the systematic benchmarking of XML query processing platforms with an initial focus on the data (versus  ...  Others focus on XML integration and restructuring with additional data-oriented functionalities such as join, nesting and aggregation as in XML -QL [31] , or partial or none of these data-oriented functionalities  ... 
doi:10.1145/502585.502614 dblp:conf/cikm/BressanDLLLNW01 fatcat:obqhleck3zexbgq6znd7whg7ke

Realization of a system of efficient querying of hierarchical data transformed into a quasi-relational model

Adam Furmanek, Jakub Tokaj, Robert Marcjan, Leszek Siwik
2016 Computer Science  
There are also many languages for querying and transforming XML, such as XPath or XQuery, which are widely used in this field.  ...  In this paper, an implementation of the SQLxD query system is proposed.  ...  Experiments have been made for three kinds of queries: • simple query with condition; • query with a simple JOIN; • complex query with two JOINS, GROUP BY phrase, and aggregate functions and three randomly  ... 
doi:10.7494/csci.2016.17.3.353 fatcat:4n32zg3z2vadpmgm4ow4q6fapq

A survey of graphical query languages for XML data

Mourad Ykhlef, Sarra Alqahtani
2011 Journal of King Saud University: Computer and Information Sciences  
In this article, we will survey some of graphical query languages for querying and restructuring XML data.  ...  Several query languages are proposed in the literature, some of them are textual query languages and some others are graphical query languages.  ...  In Table 1 we compare these graphical query languages in term of data model, path expression, grouping, aggregate functions, restructuring and querying tags.  ... 
doi:10.1016/j.jksuci.2011.05.002 fatcat:7qcs72jls5cevhwr76genpva5y

Cost Modeling and Estimation for OLAP-XML Federations [chapter]

Dennis Pedersen, Karsten Riis, Torben Bach Pedersen
2002 Lecture Notes in Computer Science  
Appendices A, B, and C contain additional detail on the OLAP component cost model, the XML component cost model, and the queries performed in the experiments, respectively.  ...  Thus, federations of OLAP and XML databases will be very attractive in many situations. However, a naive implementation of OLAP-XML federations will not perform well enough to be useful.  ...  data, namely in a decoration query (A), in a grouping query (B), and in a selection query (C).  ... 
doi:10.1007/3-540-46145-0_24 fatcat:mza4tajshrauvj2g7ivm6eajqq

Constructing an OLAP cube from distributed XML data

Tapio Niemi, Marko Niinimäki, Jyrki Nummenmaa, Peter Thanisch
2002 Proceedings of the 5th ACM international workshop on Data Warehousing and OLAP - DOLAP '02  
This data set is often huge, and it may not be known in advance what data is required and when to perform the desired data analysis tasks.  ...  As the data sources may well be heterogeneous, we propose an XML language for data collection.  ...  -Collection of the XML OLAP cube and performing necessary aggregations and selections.  ... 
doi:10.1145/583890.583894 dblp:conf/dolap/NiemiNNT02 fatcat:dzm7kt4gdzf7die5pzdmart6iu

Querying XML documents by dynamic shredding

Hui Zhang, Frank Wm. Tompa
2004 Proceedings of the 2004 ACM symposium on Document engineering - DocEng '04  
translate each XML query (e.g., expressed in W3C's XQuery) to SQL queries expressed against the shredded documents.  ...  With the wide adoption of XML as a standard data representation and exchange format, querying XML documents becomes increasingly important.  ...  Acknowledgments We gratefully acknowledge financial assistance from the University of Waterloo, Bell University Labs, and the Natural Sciences and Engineering Research Council of Canada.  ... 
doi:10.1145/1030397.1030401 dblp:conf/doceng/ZhangT04 fatcat:p7xobh64wbb4njfw66at6dg25y

Towards a hybrid relational and XML benchmark for loosely-coupled distributed data sources

Mahesh B. Chaudhari, Suzanne W. Dietrich, Jennifer Ortiz, Spencer Pearson
2015 Journal of Systems and Software  
Specifically, the paper describes the design of the relational and XML data sources as well as the query redesign in the LINQ query language, which supports queries over heterogeneous data sources.  ...  There are known benchmarks for the performance evaluation of relational and XML databases.  ...  Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.  ... 
doi:10.1016/j.jss.2015.07.029 fatcat:7xz5miqtbjcabikwdhhothvkwi

Relational extensions for OLAP

N. Colossi, W. Malloy, B. Reinwald
2002 IBM Systems Journal  
In this paper, we define meta-data extensions that allow designers of multidimensional schemas to describe the structure of those schemas to multidimensional query and analysis tools.  ...  Over time, relational database vendors have added optimizations that enhance query performance on these schemas.  ...  These queries are frequently aggregations of data, and the queries performed tend to have very similar aggregations.  ... 
doi:10.1147/sj.414.0714 fatcat:57kzuk2e5fayxmszuisr6wcfj4

Evaluating XML-extended OLAP queries based on a physical algebra

Xuepeng Yin, Torben Bach Pedersen
2004 Proceedings of the 7th ACM international workshop on Data warehousing and OLAP - DOLAP '04  
In this paper, we extend previous work on the logical federation of OLAP and XML data sources by presenting a simplified query semantics, a physical query algebra and a robust OLAP-XML query engine.  ...  Performance experiments with a prototypical implementation suggest that the performance for OLAP-XML federations is comparable to queries on physically integrated data.  ...  Finally, a SQL aggregation calculates the given aggregate functions of the measures over the grouped facts accord- ing to the SELECT and GROUP BY arguments.  ... 
doi:10.1145/1031763.1031778 dblp:conf/dolap/YinP04 fatcat:3o5gtumpcrcbnoxboclihhmevm
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