Abstract: For n fields used for grouping we can obtain 2ⁿ aggregation types. When n is not small, 2ⁿ is a considerable value. With a new model for the specification of aggregation types, we present ways in which we can obtain any subsets of aggregation types, starting from n fields used for grouping. The algorithms concern cases in which:

- The specification of aggregation types is made after we insert the data in the tables.
- The specification of aggregation types is made before we insert the data in the tables. In order to obtain the results really fast, we also use hypercubes.
- The case of one table (the fields used for grouping and for aggregation are from the same table) where we use one hypercube and we can specify the aggregation types in any moment (after or before the data insertion in the table) - model which can be used for questionnaires.

These algorithms can be used in many economic analyses, in order to obtain complex reports. We will also present an example which concerns the sales in a supermarket chain.
 

Brief Biography of the Speaker:
Mirela-Catrinel Voicu is born in Romania, 1972 and graduated in 1995 of Faculty of Mathematics and Computer Sciences, West University of Timisoara. She received the MSc degrees in Applied Mathematics, Informatics in Economy and Computer Sciences from the West University of Timisoara. She stayed for training course for PhD thesis at National Institute for Statistics and Economic Studies, Paris, France. She received her PhD in 2001 from the University of Timisoara, Romania (with the distinction “Cum laude”) and from the University of Paris 13, France (with the distinction “Très honorable avec félicitations“). Currently she is Associate Professor in the Department of Economic Informatics, Faculty of Economic Sciences, West University of Timisoara, Romania, where since 1995 she has been holding academic positions. She has teaching activity in Programming and Internet Programming, Informatics in Economy, Databases, OOP, Data structures, Exchange rate evolutions models-course. She has 59 papers in conference proceedings or refereed journals (from these papers, 11 are presented or published abroad). She has published 7 books (1 book in France and 6 books in Romania). She is reviewer and member in international program committee of 5 WSEAS conferences from abroad, member in the teams of 9 research projects (nationals and international) and project manager for one research project. Since 2002, she is member INFOREC (Romanian Association for Economic Informatics Training Promotion) and since 2005 is member WSEAS (World Scientific And Engineering Academy And Society).