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Generating Multidimensional Schemata from Relational Aggregation Queries [chapter]

Chaoyi Pang, Kerry Taylor, Xiuzhen Zhang, Mark Cameron
2004 Lecture Notes in Computer Science  
from.  ...  We propose to use such queries to automatically generate measures, dimensions and dimension hierarchies and their representation in a star schema.  ...  When new demands occur, our design methodology can evolve the previously generated schemata into new schemata by integrating the new queries interpreted from the demands [12] .  ... 
doi:10.1007/978-3-540-30480-7_60 fatcat:gnexbuf5onhi7kdvhrrfqef6ua

New Frontiers in Business Intelligence: Distribution and Personalization [chapter]

Stefano Rizzi
2010 Lecture Notes in Computer Science  
Then we discuss some issues related to OLAP query reformulation on peers, showing how it can be achieved using semantic mappings between the local multidimensional schemata of peers.  ...  To meet the new, more sophisticated needs of decision makers, a new generation of BI systems is emerging.  ...  The language we propose to express how the local multidimensional schemata of p maps onto the one of q includes five mapping predicates, namely same, equi-level, roll-up, drilldown, and related.  ... 
doi:10.1007/978-3-642-15576-5_4 fatcat:vw3x3ts4f5cpvb7jye4eahm45a

Collaborative Business Intelligence [chapter]

Stefano Rizzi
2012 Lecture Notes in Business Information Processing  
Then we outline a new peer-to-peer framework, called Business Intelligence Network, where peers expose querying functionalities aimed at sharing business information for the decision-making process.  ...  As to multidimensional schemata, without loss of generality we assume that they are stored at the relational level as star schemata.  ...  Multidimensional schemata of related facts at two peers defined to reformulate queries expressed in London (target peer) according to the schema adopted in Rome (source peer).  ... 
doi:10.1007/978-3-642-27358-2_9 fatcat:dcxgdkaz2rdm7edfac5tcjrc4i

OLAP query reformulation in peer-to-peer data warehousing

M. Golfarelli, F. Mandreoli, W. Penzo, S. Rizzi, E. Turricchia
2012 Information Systems  
, queries, and multidimensional schemata onto the relational level.  ...  To enhance the decision making process, an OLAP query expressed on a peer needs to be properly reformulated on the local multidimensional schemata of the other peers.  ...  , queries, and multidimensional schemata onto the relational level.  ... 
doi:10.1016/ fatcat:obhru4n3lvbnjbuupivdgjbuxm


Sandro Bimonte, Elodie Edoh-alove, Hassan Nazih, Myoung-Ah Kang, Stefano Rizzi
2013 Proceedings of the sixteenth international workshop on Data warehousing and OLAP - DOLAP '13  
., without visualizing sample results of queries, which in turn would require availability of source data.  ...  To solve this deadlock we propose ProtOLAP, a toolassisted fast prototyping methodology that enables quick and reliable test and validation of data warehouse schemata in situations where data supply is  ...  Here, a logical (relational) schema and the related metadata are automatically generated and deployed starting from the conceptual schema.  ... 
doi:10.1145/2513190.2513199 dblp:conf/dolap/BimonteENKR13 fatcat:jldrrpeldzhn7kv53wqxbzltja

Towards OLAP query reformulation in peer-to-peer data warehousing

Matteo Golfarelli, Federica Mandreoli, Wilma Penzo, Stefano Rizzi, Elisa Turricchia
2010 Proceedings of the ACM 13th international workshop on Data warehousing and OLAP - DOLAP '10  
these mappings towards relational schemata.  ...  In this direction, we present a language for the definition of mappings between the multidimensional schemata of peers, and we introduce a query reformulation framework that relies on the translation of  ...  the other peers in terms of their own multidimensional schemata. (3) Each involved peer locally processes the reformulated query and returns its results to the querying peer. (4) Finally, the results  ... 
doi:10.1145/1871940.1871950 dblp:conf/dolap/GolfarelliMPRT10 fatcat:nuyahcvedjcvzjtnihe6yxqpvm

Bridging the semantic gap in OLAP models

Jesús Pardillo, Jose-Norberto Mazón, Juan Trujillo
2008 Proceeding of the ACM 11th international workshop on Data warehousing and OLAP - DOLAP '08  
The great advantage of our approach is that we allow analysts to query data warehouses without being aware of logical details.  ...  In order to bridge this gap, we propose the use of conceptual OLAP queries, i.e., platformindependent, that can be automatically traced to their logical implementation in a coherent and integrated way.  ...  snowflake logical schemata in a SQL-based relational platform.  ... 
doi:10.1145/1458432.1458448 dblp:conf/dolap/PardilloMT08 fatcat:6ky7fflxl5b6bfbt7qpm7rhlae

Research in data warehouse modeling and design

Stefano Rizzi, Alberto Abelló, Jens Lechtenbörger, Juan Trujillo
2006 Proceedings of the 9th ACM international workshop on Data warehousing and OLAP - DOLAP '06  
Multidimensional modeling requires specialized design techniques. Though a lot has been written about how a data warehouse should be designed, there is no consensus on a design method yet.  ...  This paper follows from a wide discussion that took place in Dagstuhl, during the Perspectives Workshop "Data Warehousing at the Crossroads", and is aimed at outlining some open issues in modeling and  ...  For instance, two queries obtained one from another through a simple drill-down operation (thus differing only in their aggregation levels) may involve the same table, rows, and columns, though the one  ... 
doi:10.1145/1183512.1183515 dblp:conf/dolap/RizziALT06 fatcat:yobwuku7tnfblbjxn7f6bvfpz4

Integrating Data Warehouses with Web Data: A Survey

J.M. Perez, R. Berlanga, M.J. Aramburu, T.B. Pedersen
2008 IEEE Transactions on Knowledge and Data Engineering  
It studies the XML technologies that are currently being used to integrate, store, query, and retrieve Web data and their application to DWs.  ...  It studies Web data repositories, the design of multidimensional databases for XML data sources, and the XML extensions of OnLine Analytical Processing techniques.  ...  Multi-Dimensional eXpressions (MDX) [37] is the most used query language for reporting from multidimensional data stores.  ... 
doi:10.1109/tkde.2007.190746 fatcat:drcxlccqqfaifcjuzbzspyzlpu

CubeLoad: A Parametric Generator of Realistic OLAP Workloads [chapter]

Stefano Rizzi, Enrico Gallinucci
2014 Lecture Notes in Computer Science  
Differently from OLTP workloads, OLAP workloads are hardly predictable due to their inherently extemporary nature.  ...  Besides, obtaining real OLAP workloads by monitoring the queries actually issued in companies and organizations is quite hard.  ...  -The workload is generated in the form of sessions, each including a variable number of aggregate queries. The main parameters used are related to a realistic profile-based workload model.  ... 
doi:10.1007/978-3-319-07881-6_41 fatcat:vma5oxdna5d2jm37v2kjjqrcoq

Towards a logical multidimensional model for spatial data warehousing and OLAP

Marcus Costa Sampaio, André Gomes de Sousa, Cláudio de Souza Baptista
2006 Proceedings of the 9th ACM international workshop on Data warehousing and OLAP - DOLAP '06  
This paper proposes a novel logical multidimensional model suitable for SDW, which is implemented on the top of an object-relational database system with support for spatial data.  ...  Moreover, the paper addresses query optimization techniques to enhance performance and it describes a prototype, which has been built to validate the proposed ideas.  ...  The reason for this choice is that SDW implementation brings interesting open problems, related to spatial multidimensional query performance.  ... 
doi:10.1145/1183512.1183528 dblp:conf/dolap/SampaioSB06 fatcat:idcob6wyljc2fjw7cr27fre6ii

A Survey on Temporal Data Warehousing

Matteo Golfarelli, Stefano Rizzi
2009 International Journal of Data Warehousing and Mining  
His current research interests include data warehouse design and business intelligence, in particular multidimensional modeling, data warehouse evolution, OLAP preferences and what-if analysis.  ...  with reference to a three-levels architecture, these issues can be classified into some topics, namely: handling data/schema changes in the data warehouse, handling data/schema changes in the data mart, querying  ...  Feng, Li, Agrawal, & El Abbadi (2005) proposed a general approach to improve the efficiency of range aggregate queries on MOLAP data cubes in a temporal data warehouse by separately handling timerelated  ... 
doi:10.4018/jdwm.2009010101 fatcat:3ct6dsb7xrbjlgipnup43n4ode

Constructing OLAP cubes based on queries

Tapio Niemi, Jyrki Nummenmaa, Peter Thanisch
2001 Proceedings of the 4th ACM international workshop on Data warehousing and OLAP - DOLAP '01  
The method constructs complete but minimal cubes with low risks related to sparsity and incorrect aggregations. After the user has given queries, the system will suggest a cube design.  ...  Although their details are not known in advance, the general form of those queries is apparent beforehand.  ...  Example 2 An MDX query related to the schema in CONSTRUCTING CUBES To construct an OLAP cube we need to detect the measure(s) and the dimensions from the set of example MDX queries.  ... 
doi:10.1145/512236.512238 dblp:conf/dolap/NiemiNT01 fatcat:qylutddgardgtotrdvqeegc5vu

A Decathlon in Multidimensional Modeling: Open Issues and Some Solutions [chapter]

W. Hümmer, W. Lehner, A. Bauer, L. Schlesinger
2002 Lecture Notes in Computer Science  
In this paper we address ten common problems reaching from defects within dimensional structures over multidimensional structures to new analytical requirements and more.  ...  In discussing the current state-of-the-art we are far from producing the ultimate solutions of these problems.  ...  Although these operations are not yet fully standardized, the problems arising from sequence oriented queries in the relational area are well studied and many concepts are published (e.g.  ... 
doi:10.1007/3-540-46145-0_27 fatcat:reydox6ykbgy7a3mqpself543u

Using Perspective Schemata To Model The Etl Process

Valeria M. Pequeno, Joao Carlos G. M. Pires
2009 Zenodo  
The data must be Extracted from information sources, Transformed and integrated to be Loaded (ETL) into the DW, using ETL tools.  ...  This paper presents the overview of the proposed framework to model the ETL process, which is based on the use of a reference model and perspective schemata.  ...  generate a new perspective schema from the source schemata to the data warehouse one.  ... 
doi:10.5281/zenodo.1071869 fatcat:eqcre6zho5g4vg2azk3smqrzte
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