Modélisation et extraction de données pour un entrepôt objet

National audienceThis paper describes an object-oriented model for designing complex and time-variant data warehouse data. The main contribution is the warehouse class concept, which extends the class concept by temporal and archive filters as well as a mapping function. Filters allow the keeping of relevant data changes whereas the mapping function defines the warehouse class schema from a global data source schema. The approach take into account static properties as well as dynamic properties. The behaviour extraction is based on the use-matrix concept

Modélisation des transformations pour l'évolution de modèles multidimensionnels

La modélisation et l'entreposage des données ont constitué, depuis plus d'une décennie, une problématique de recherche pour laquelle différentes approches ont été proposées. Ces approches se focalisent sur des aspects statiques de l'entrepôt de données. Or, l'évolution du système d'information qui alimente un entrepôt peut avoir un impact sur ce dernier et peut conduire, par conséquent, à l'évolution de son modèle multidimensionnel. Dans ce contexte évolutif, nous proposons une démarche dirigée par les modèles pour automatiser la propagation de l'évolution du modèle de la source de données relationnelle vers l'entrepôt. Cette démarche est fondée sur deux modèles d'évolution ainsi qu'un ensemble de règles de transformation formalisées en Query/View/Transformation. Nous développons un prototype logiciel nommé DWE (« Data Warehouse Evolution ») qui supporte cette démarche

Xml warehouse modelling and queryinq

International audienceIntegrating XML documents in data warehouse is a major issue for decisional data processing and business intelligence. Indeed this type of data is increasingly being used in organisations’ information system. But the current warehousing systems do not manage documents as they do for extracted data from relational databases. We have therefore developed a multidimensional model based on the Unified Modeling Language (UML), to describe an XML Document Warehouse (XDW). The warehouse diagram obtained is a Star schema ( StarCD) which fact represents the documents class to be analyzed, and the dimensions correspond to analysis criteria extracted from the structure of the documents. The standard XQuery language can express queries on XML documents, but it is not suitable for analyzing a warehouse as its syntax is too complex for a non IT specialist. This paper presents a new language aimed at decision-makers and allows applying OLAP queries on a XDW described by a StarCD

Personnalisation de bases de données multidimensionnelles

National audienceThis paper deals with decision support systems resting on multidimensional modelling of data. Moreover, we intend to offer a set of concepts and mechanisms for personalized multidimensional database specifications. This personalization consists in associating weights to different components of a multidimensional schema. Personalization specifications are specified through the use of a language based on the principle of Event Condition Action. This personalisation determines multidimensional data display as well as their analyses (with the use of drilling or rotating operations)

Algèbre OLAP et langage graphique

National audienceThis article deals with OLAP systems based on multidimensional model. The conceptual model we provide, represents data through a constellation (multi-facts) composed of several multi-hierarchy dimensions. In this model, data are displayed through multidimensional tables. We define a query algebra handling these tables. This user oriented algebra is composed of a closure core of OLAP operators as soon as advanced operators dedicated to complex analysis. Finally, we specify a graphical OLAP language based on this algebra. This language facilitates analyses of decision makers

Galaxy-Gen: A Tool for Building Galaxy model from XML documents

National audienceA galaxy model is a multidimensional model dedicated for XML document warehouses. It can be seen as a network of entities (i.e., dimensions) connected via nodes. After giving an overview of our four-steps semi-automated method for the generation of galaxy models which aims to build data marts from XML documents. This paper focuses on the software tool, called Galaxy-Gen that implements the proposed method. We illustrate the Galaxy-Gen functionalities and make its first assessment through two experiments. The first experiment is applied to a set of twenty XML documents taken from the academic domain. The second one addressed a set of 1691 XML documents issued from the Clef-2007 collection. The assessment is performed by comparing manual design galaxy models with those produced by the Galaxy-Gen tool. The results are very promising

Méthode de Développement des Systèmes d'Information Décisionnels : Roue de Deming

National audienceID6, a company specialized in decisional support systems (DSS), requested a development method for such systems. This method must achieve a fast development of reliable DSS according to user requirements in a context oriented reuse. None of the existing DSS-specific methods has become a standard. Moreover, they do not favor reuse of knowledge. In order to take advantages of our convention with I-D6, we decided to define a method according to Deming Wheel. For the four iterations of our method definition, we use the Deming cycle. We present in this paper the process of our method definition according to Deming Wheel

Contraintes pour modèle et langage multidimensionnels

National audienceThis paper defines a constraint-based model dedicated to multidimensional databases. The model we define represents data through a constellation of facts (subjects of analyse) associated to dimensions (axis of analyse), which are possibly shared. Each dimension is organised according to several hierarchies (views of analyse) integrating several levels of data granularity. In order to insure data consistency, we introduce 5 semantic constraints (exclusion, inclusion, partition, simultaneity, totality) which can be intra-dimension or inter-dimensions; the intra-dimension constraints allow the expression of constraints between hierarchies within a same dimension whereas the inter-dimensions constraints focus on hierarchies of distinct dimensions. We also study repercussions of these constraints on multidimensional manipulations and we provide extensions of the multidimensional operators

Conception assistée d'entrepôts de données et de documents XML pour l'analyse OLAP

Aujourd hui, les entrepôts de données constituent un enjeu majeur pour les applications décisionnelles au sein des entreprises. Les sources d un entrepôt, c est à dire l origine des données qui l alimentent, sont diverses et hétérogènes : fichiers séquentiels, feuilles de tableur, bases de données relationnelles, documents du Web. La complexité est telle que les logiciels du marché ne répondent que partiellement aux attentes des décideurs lorsque ceux-ci souhaitent analyser les données. Nos travaux s inscrivent donc dans le contexte des systèmes décisionnels qui intègrent tous types de données (principalement extraites de bases de données relationnelles et de bases de documents XML) et qui sont destinés à des décideurs. Ils visent à proposer des modèles, des méthodes et des outils logiciels pour élaborer et manipuler des entrepôts de données. Nos travaux ont plus précisément porté sur deux problématiques complémentaires : l élaboration assistée d un entrepôt de données ainsi que la modélisation et l analyse OLAP de documents XML.Today, data warehouses are a major issue for business intelligence applications within companies. Sources of a warehouse, i.e. the origin of data that feed, are diverse and heterogeneous sequential files, spreadsheets, relational databases, Web documents. The complexity is such that the software on the market only partially meets the needs of decision makers when they want to analyze the data. Therefore, our work is within the decision support systems context that integrate all data types (mainly extracted from relational databases and XML documents databases) for decision makers. They aim to provide models, methods and software tools to elaborate and manipulate data warehouses. Our work has specifically focused on two complementary issues: aided data warehouse and modeling and OLAP analysis of XML documents.TOULOUSE1-SCD-Bib. electronique (315559902) / SudocSudocFranceF