OLAP Hierarchies: A Conceptual Perspective

OLAP (On-Line Analytical Processing) tools support the decision-making process by giving users the possibility to dynamically analyze high volumes of historical data using operations such as roll-up and drill-down. These operations need well-defined hierarchies in order to prepare automatic calculations. However, many kinds of complex hierarchies arising in real-world situations are not addressed by current OLAP implementations. Based on an analysis of real-world applications and scientific works related to multidimensional modeling, this paper presents a conceptual classification of hierarchies and proposes graphical notations for them based on the ER model. A conceptual representation of hierarchies allows the designer to properly represent users’ requirements in multidimensional modeling and offers a common vision of these hierarchies for conceptual modeling and OLAP tools implementers.

[1]  Arie Shoshani,et al.  Summarizability in OLAP and statistical data bases , 1997, Proceedings. Ninth International Conference on Scientific and Statistical Database Management (Cat. No.97TB100150).

[2]  Riccardo Torlone.  Conceptual Multidimensional Models , 2003, Multidimensional Databases.

[3]  Timos K. Sellis,et al.  MAC: Conceptual data modeling for OLAP , 2001, DMDW.

[4]  Alberto Abelll.  YAM 2 ( Yet Another Multidimensional Model ) : An extension of UMLAlberto Abell , .

[5]  Zhang Hengxi,et al.  A Methodological Framework for Data Warehouse Design , 2003 .

[6]  Il-Yeol Song,et al.  Multidimensional Modeling with UML Package Diagrams , 2002, ER.

[7]  Barbara Dinter,et al.  Extending the E/R Model for the Multidimensional Paradigm , 1998, ER Workshops.

[8]  Stefano Rizzi.  Open problems in data warehousing: eight years later , 2003, DMDW.

[9]  Ivar Jacobson,et al.  The Unified Modeling Language User Guide , 1998, J. Database Manag..

[10]  Janet Balas,et al.  Books online , 1993 .

[11]  Wolfgang Lehner,et al.  Normal forms for multidimensional databases , 1998, Proceedings. Tenth International Conference on Scientific and Statistical Database Management (Cat. No.98TB100243).

[12]  Christian S. Jensen,et al.  A foundation for capturing and querying complex multidimensional data , 2001, Inf. Syst..

[13]  Gottfried Vossen,et al.  Conceptual Data Warehouse Design , 2000 .

[14]  Alberto O. Mendelzon,et al.  Reasoning about Summarizability in Heterogeneous Multidimensional Schemas , 2001, ICDT.

[15]  Luca Cabibbo,et al.  The Design and Development of a Logical System for OLAP , 2000, DaWaK.

[16]  Nectaria Tryfona,et al.  starER: a conceptual model for data warehouse design , 1999, DOLAP '99.

[17]  Wolfgang Lehner,et al.  An Alternative Relational OLAP Modeling Approach , 2000, DaWaK.

[18]  Laks V. S. Lakshmanan,et al.  What can Hierarchies do for Data Warehouses? , 1999, VLDB.

[19]  Francisco Charte.  SQL Server 2000 , 2001 .

[20]  Ralph Kimball,et al.  The Data Warehouse Toolkit: The Complete Guide to Dimensional Modeling , 1996 .

[21]  Elaheh Pourabbas,et al.  Characterization of hierarchies and some operators in OLAP environment , 1999, DOLAP '99.

[22]  PedersenTorben Bach,et al.  A foundation for capturing and querying complex multidimensional data , 2001 .

[23]  Ivar Jacobson,et al.  Unified Modeling Language , 2020, Definitions.

[24]  Alberto O. Mendelzon,et al.  OLAP dimension constraints , 2002, PODS '02.