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Heuristic optimization of OLAP queries in multidimensionally hierarchically clustered databases

Dimitri Theodoratos, Aris Tsois
2001 Proceedings of the 4th ACM international workshop on Data warehousing and OLAP - DOLAP '01  
Then, we focus on heuristically optimizing OLAP queries over this schema using multidimensional access methods.  ...  We exploit the different clustering features of the CSB star to efficiently process a class of typical OLAP queries.  ...  Contribution In this paper we focus on heuristically optimizing OLAP queries in databases that are clustered with respect to multiple hierarchical dimensions using multidimensional access methods.  ... 
doi:10.1145/512236.512243 dblp:conf/dolap/TheodoratosT01 fatcat:3a2xvdkkeffttpim5qg72eddxa

Processing Star Queries on Hierarchically-Clustered Fact Tables [chapter]

Nikos Karayannidis, Aris Tsois, Timos Sellis, Roland Pieringer, Volker Markl, Frank Ramsak, Robert Fenk, Klaus Elhardt, Rudolf Bayer
2002 VLDB '02: Proceedings of the 28th International Conference on Very Large Databases  
Star queries are the most prevalent kind of queries in data warehousing, OLAP and business intelligence applications. Thus, there is an imperative need for efficiently processing star queries.  ...  In this paper, we present a complete abstract processing plan that captures all the necessary steps in evaluating such queries over hierarchically clustered fact tables.  ...  Optimization of the h-surrogate processing phase Hierarchical surrogate keys play a dominating role in the processing of star queries over hierarchically clustered multidimensional data with hierarchies  ... 
doi:10.1016/b978-155860869-6/50070-6 dblp:conf/vldb/KarayannidisTSPMRFEB02 fatcat:uv7s77uizrat3ecxeijpayd53u

An Architecture for Integrated Online Analytical Mining

Muhammad Usman, Sohail Asghar
2011 Journal of Emerging Technologies in Web Intelligence  
In the proposed work, hierarchical clustering has been used as the data mining technique and three types of schemas namely star, snowflake and galaxy were automatically generated.  ...  We enhanced the performance of OLAP in terms of cube construction time and visualization by providing interactive visual exploration of data cube.  ...  In the same context, Theodoratos et al. [32] claimed the Heuristic Optimization of OLAP in MHC (Multidimensionally Hierarchically Clustered) databases.  ... 
doi:10.4304/jetwi.3.2.74-99 fatcat:ppkarvwrojho5ftwdwqqok2m6m

Topic Cube: Topic Modeling for OLAP on Multidimensional Text Databases [chapter]

Duo Zhang, Chengxiang Zhai, Jiawei Han
2009 Proceedings of the 2009 SIAM International Conference on Data Mining  
In this paper, we propose a new data model called topic cube to combine OLAP with probabilistic topic modeling and enable OLAP on the dimension of text data in a multidimensional text database.  ...  Experiment results show that this heuristic method is much faster than the baseline method of computing each topic cube from scratch.  ...  The work was supported in part by NASA grant NNX08AC35A, the U.S.  ... 
doi:10.1137/1.9781611972795.96 dblp:conf/sdm/ZhangZH09 fatcat:5jwos3sgvnekzkmfrbr634ty5y

Topic modeling for OLAP on multidimensional text databases: topic cube and its applications

Duo Zhang, ChengXiang Zhai, Jiawei Han, Ashok Srivastava, Nikunj Oza
2009 Statistical analysis and data mining  
In this paper, we propose a new data model called topic cube to combine OLAP with probabilistic topic modeling and enable OLAP on the dimension of text data in a multidimensional text database.  ...  Experiment results show that these heuristic aggregations are much faster than the baseline method of computing each topic cube from scratch.  ...  Acknowledgment The work was supported in part by NASA grant NNX08AC35A, the U.S.  ... 
doi:10.1002/sam.10059 fatcat:b7mpn3tahrg4dna4y7yymeo56y

Honey, I Shrunk the Cube [chapter]

Matteo Golfarelli, Stefano Rizzi
2013 Lecture Notes in Computer Science  
databases  An OLAP query asks for returning the values of one or more numerical measures, grouped by a given set of analysis attributes  An OLAP analysis is typically composed by a sequence of queries  ...   Motivating scenario  The shrink approach  A Heuristic algorithm for shrinking  Experimental results  Summary and future work DW & OLAP Analysis  OLAP is the main paradigm for querying multidimensional  ...  A heuristic approach is needed to satisfy the real-time computation required in OLAP  We adopted an agglomerative hierarchical clustering algorithm with constraints  the algorithm starts from a clustering  ... 
doi:10.1007/978-3-642-40683-6_14 fatcat:zgxwlu2urjd4hozkye3kymdkhe

CUBE File: A File Structure for Hierarchically Clustered OLAP Cubes [chapter]

Nikos Karayannidis, Timos Sellis, Yannis Kouvaras
2004 Lecture Notes in Computer Science  
Hierarchical clustering has been proved an effective means for physically organizing large fact tables since it reduces significantly the I/O cost during ad hoc OLAP query evaluation.  ...  In this paper, we propose a novel multidimensional file structure for organizing the most detailed data of a cube, the CUBE File.  ...  Introduction On Line Analytical Processing (OLAP) has caused a significant shift in the traditional database query paradigm.  ... 
doi:10.1007/978-3-540-24741-8_36 fatcat:ujpbpl5vorfajfp3ei757nujci

Integration of Data Mining and Data Warehousing: A Practical Methodology

Muhammad Usman, Russel Pears
2010 International Journal of Advancements in Computing Technology  
Little research has been carried out in tackling the problem of clustering high cardinality nominal variables to get better insight of underlying dataset.  ...  Results show that multidimensional analysis can be performed in an easier and flexible way to discover meaningful knowledge from large datasets.  ...  derivation of OLAP metadata in a way that is integrated with database schema.  ... 
doi:10.4156/ijact.vol2.issue3.4 fatcat:jsmrrhak3vhefl2psd6wewstta

OLAP and statistical databases

Arie Shoshani
1997 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems - PODS '97  
Examples of SDBs and OLAP Databases We describe in this section an example of the traditional 2dimensional (2-D) representation of SDBs, followed by a data cube representation of OLAP databases, and show  ...  Much of the work on SDBs took place in the 1980's but continues till today, while OLAP database work started mostly in the 1990's.  ...  Acknowledgment This work is supported by the of Energy Research, U.S. Department of Energy under Contract DE-AC03-76SF00098.  ... 
doi:10.1145/263661.263682 dblp:conf/pods/Shoshani97 fatcat:nnwnpitmufdazda7yjhdk3pl4y

A Relational Data Warehouse for Multidimensional Process Mining [chapter]

Thomas Vogelgesang, H.-Jürgen Appelrath
2017 Lecture Notes in Business Information Processing  
Based on a relational database schema, we introduce generic query patterns which map OLAP queries to SQL to push the operations (i.e. aggregation and filtering) to the database management system.  ...  In this paper, we present the underlying relational concepts of PMCube, a datawarehouse-based approach for multidimensional process mining.  ...  Multidimensional OLAP (MOLAP) approaches rely on a mainly memory-based multidimensional array storage. Relational OLAP (ROLAP) maps the multidimensional data to a relational database schema.  ... 
doi:10.1007/978-3-319-53435-0_8 fatcat:4f7yg45jxvahfive6srypbsiji

Fragmenting very large XML data warehouses via K-means clustering algorithm

Alfredo Cuzzocrea, Jerome Darmont, Hadj Mahboubi
2009 International Journal of Business Intelligence and Data Mining  
However, XML-native database systems currently suffer from limited performance, both in terms of volumes of manageable data and query response time.  ...  XML data sources are more and more gaining popularity in the context of a wide family of Business Intelligence (BI) and On-Line Analytical Processing (OLAP) applications, due to the amenities of XML in  ...  Overall, this allows us to model an OLAP hierarchical level in all its characteristics and values.  ... 
doi:10.1504/ijbidm.2009.029076 fatcat:wve3gtsfmnccvl2mnrp3q7ft3e

Data mining-based fragmentation of XML data warehouses

Hadj Mahboubi, Jérôme Darmont
2008 Proceeding of the ACM 11th international workshop on Data warehousing and OLAP - DOLAP '08  
However, XML-native database systems currently suffer from limited performances, both in terms of manageable data volume and response time. Fragmentation helps address both these issues.  ...  In this paper, we propose the use of a k-means-based fragmentation approach that allows to master the number of fragments through its k parameter.  ...  ACKNOWLEDGMENTS The authors would like to thank Houssem Aissa, Anouar Benzakour, Kevin du Repaire and Hamza El Kartite, who participated in coding our approach in Java.  ... 
doi:10.1145/1458432.1458435 dblp:conf/dolap/MahboubiD08 fatcat:zeypfx4hq5c5nis3sh44tf6oem

The workload you have, the workload you would like

Matteo Golfarelli, Ettore Saltarelli
2003 Proceedings of the 6th ACM international workshop on Data warehousing and OLAP - DOLAP '03  
The ability of the profile to characterize a workload is then exploited to move backward using it as an input for an algorithm that generates a set of queries presenting the desired features.  ...  In this paper we propose the idea of profile as an instrument for summarizing the workload features in order to help the designer to make the right choices.  ...  In our test we adopted the clustering algorithm proposed in [4] that is based on a hierarchical approach that recursively agglomerates the two most similar clusters that contain one single query at the  ... 
doi:10.1145/956073.956075 fatcat:3pw7ogrgbjayhlzufjk774k4y4

The workload you have, the workload you would like

Matteo Golfarelli, Ettore Saltarelli
2003 Proceedings of the 6th ACM international workshop on Data warehousing and OLAP - DOLAP '03  
The ability of the profile to characterize a workload is then exploited to move backward using it as an input for an algorithm that generates a set of queries presenting the desired features.  ...  In this paper we propose the idea of profile as an instrument for summarizing the workload features in order to help the designer to make the right choices.  ...  In our test we adopted the clustering algorithm proposed in [4] that is based on a hierarchical approach that recursively agglomerates the two most similar clusters that contain one single query at the  ... 
doi:10.1145/956060.956075 dblp:conf/dolap/GolfarelliS03 fatcat:szmocvwzhjhqjp5tomxkjz7xk4

Automatically generating OLAP schmata from conceptual graphical models

Karl Hahn, Carsten Sapia, Markus Blaschka
2000 Proceedings of the 3rd ACM international workshop on Data warehousing and OLAP - DOLAP '00  
Generating tool specific schemata and configuration information for OLAP database tools from conceptual graphical models is an important prerequisite for a comprehensive tool support for computer aided  ...  This paper describes the design and implementation of such a generation component in the context of our BabelFish data warehouse design tool environment.  ...  A typical OLAP query against this schema could be: "show me the total costs of all vehicle repairs of make BMW in the last month".  ... 
doi:10.1145/355068.355310 dblp:conf/dolap/HahnSB00 fatcat:w2gy7esdgrguve3umrk72gm6sa
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