General Model for Data Warehouses

2011 ◽  
pp. 523-528
Author(s):  
Michel Schneider
Keyword(s):  
Data Warehouse ◽  
General Model ◽  
Mineral Water ◽  
Product Type ◽  
The Other ◽  
Aggregation Function ◽  
Data Warehouses ◽  
Other Hand ◽  
One Year ◽  
Aggregation Operations

Basically, the schema of a data warehouse lies on two kinds of elements: facts and dimensions. Facts are used to memorize measures about situations or events. Dimensions are used to analyse these measures, particularly through aggregation operations (counting, summation, average, etc.). To fix the ideas let us consider the analysis of the sales in a shop according to the product type and to the month in the year. Each sale of a product is a fact. One can characterize it by a quantity. One can calculate an aggregation function on the quantities of several facts. For example, one can make the sum of quantities sold for the product type “mineral water” during January in 2001, 2002 and 2003. Product type is a criterion of the dimension Product. Month and Year are criteria of the dimension Time. A quantity is so connected both with a type of product and with a month of one year. This type of connection concerns the organization of facts with regard to dimensions. On the other hand a month is connected to one year. This type of connection concerns the organization of criteria within a dimension. The possibilities of fact analysis depend on these two forms of connection and on the schema of the warehouse. This schema is chosen by the designer in accordance with the users needs.

A General Model for Data Warehouses

2011 ◽  
pp. 913-919
Author(s):  
Michel Schneider
Keyword(s):  
Data Warehouse ◽  
General Model ◽  
Mineral Water ◽  
Product Type ◽  
The Other ◽  
Aggregation Function ◽  
Data Warehouses ◽  
Other Hand ◽  
One Year ◽  
Aggregation Operations

Basically, the schema of a data warehouse lies on two kinds of elements: facts and dimensions. Facts are used to memorize measures about situations or events. Dimensions are used to analyse these measures, particularly through aggregation operations (counting, summation, average, etc.). To fix the ideas let us consider the analysis of the sales in a shop according to the product type and to the month in the year. Each sale of a product is a fact. One can characterize it by a quantity. One can calculate an aggregation function on the quantities of several facts. For example, one can make the sum of quantities sold for the product type “mineral water” during January in 2001, 2002 and 2003. Product type is a criterion of the dimension Product. Month and Year are criteria of the dimension Time. A quantity is so connected both with a type of product and with a month of one year. This type of connection concerns the organization of facts with regard to dimensions. On the other hand a month is connected to one year. This type of connection concerns the organization of criteria within a dimension. The possibilities of fact analysis depend on these two forms of connection and on the schema of the warehouse. This schema is chosen by the designer in accordance with the users needs. Determining the schema of a data warehouse cannot be achieved without adequate modelling of dimensions and facts. In this article we present a general model for dimensions and facts and their relationships. This model will facilitate greatly the choice of the schema and its manipulation by the users.

Analyses and Evaluation of Responses to Slowly Changing Dimensions in Data Warehouses

2011 ◽  
pp. 324-337
Author(s):  
Lars Frank ◽  
Christian Frank
Keyword(s):  
Data Warehouse ◽  
Concurrency Control ◽  
The Other ◽  
Data Warehouses ◽  
Other Hand ◽  
Star Schema ◽  
Dynamic Dimension ◽  
Special Case

A Star Schema Data Warehouse looks like a star with a central, so-called fact table, in the middle, surrounded by so-called dimension tables with one-to-many relationships to the central fact table. Dimensions are defined as dynamic or slowly changing if the attributes or relationships of a dimension can be updated. Aggregations of fact data to the level of the related dynamic dimensions might be misleading if the fact data are aggregated without considering the changes of the dimensions. In this chapter, we will first prove that the problems of SCD (Slowly Changing Dimensions) in a datawarehouse may be viewed as a special case of the read skew anomaly that may occur when different transactions access and update records without concurrency control. That is, we prove that aggregating fact data to the levels of a dynamic dimension should not make sense. On the other hand, we will also illustrate, by examples, that in some situations it does make sense that fact data is aggregated to the levels of a dynamic dimension. That is, it is the semantics of the data that determine whether historical dimension data should be preserved or destroyed. Even worse, we also illustrate that for some applications, we need a history preserving response, while for other applications at the same time need a history destroying response. Kimball et al., (2002), have described three classic solutions/responses to handling the aggregation problems caused by slowly changing dimensions. In this chapter, we will describe and evaluate four more responses of which one are new. This is important because all the responses have very different properties, and it is not possible to select a best solution without knowing the semantics of the data.

A Survey of Parallel and Distributed Data Warehouses

2010 ◽  
pp. 865-886
Author(s):  
Pedro Furtado
Keyword(s):  
Data Warehouse ◽  
The Other ◽  
Distributed Data ◽  
Data Warehouses ◽  
Research Results ◽  
Other Hand ◽  
Scientific Organizations ◽  
Globalized World ◽  
Distributed Data Warehouse

Data Warehouses are a crucial technology for current competitive organizations in the globalized world. Size, speed and distributed operation are major challenges concerning those systems. Many data warehouses have huge sizes and the requirement that queries be processed quickly and efficiently, so parallel solutions are deployed to render the necessary efficiency. Distributed operation, on the other hand, concerns global commercial and scientific organizations that need to share their data in a coherent distributed data warehouse. In this article we review the major concepts, systems and research results behind parallel and distributed data warehouses.

A Survey of Parallel and Distributed Data Warehouses

2011 ◽  
pp. 148-169
Author(s):  
Pedro Furtado
Keyword(s):  
Data Warehouse ◽  
The Other ◽  
Distributed Data ◽  
Data Warehouses ◽  
Research Results ◽  
Other Hand ◽  
Scientific Organizations ◽  
Globalized World ◽  
Distributed Data Warehouse

Data Warehouses are a crucial technology for current competitive organizations in the globalized world. Size, speed and distributed operation are major challenges concerning those systems. Many data warehouses have huge sizes and the requirement that queries be processed quickly and efficiently, so parallel solutions are deployed to render the necessary efficiency. Distributed operation, on the other hand, concerns global commercial and scientific organizations that need to share their data in a coherent distributed data warehouse. In this article we review the major concepts, systems and research results behind parallel and distributed data warehouses.

Blackout: How Long, O Lord, How Long?

2012 ◽  
pp. 419-440
Author(s):  
Maurice N. Eisendrath
Keyword(s):  
United States ◽  
The United States ◽  
The Other ◽  
The South ◽  
The Third ◽  
Eastern Front ◽  
Other Hand ◽  
War Effort ◽  
British Commonwealth ◽  
One Year

This chapter presents a sermon by Maurice N. Eisendrath, delivered on the third Rosh Hashanah of the war. The situation of Canadian rabbis was precariously positioned between those of American preachers to the south and British preachers to the east. Canada, as part of the British Commonwealth, had long been part of the war effort, so the debate over whether or not to enter the war was not an issue, as it still was for colleagues in the United States. On the other hand, Canada was not directly affected by the war as was Britain, where one year earlier London had suffered a sustained air attack unprecedented in its devastation (a situation that certainly affected the mood in Toronto on the previous Rosh Hashanah, as the preacher reminds his listeners). Now, although the battles on the recently opened Eastern Front were of almost unimaginable ferocity, to many Canadians the war seemed distant; life at home seemed almost normal, as it did to many in the United States. This was precisely the mindset that Eisendrath set out to censure.

Concluding remarks

1958 ◽  
Vol 246 (1247) ◽  
pp. 490-494
Keyword(s):  
Parity Violation ◽  
Present Approach ◽  
The Other ◽  
Clear Picture ◽  
Present Stage ◽  
Amount Of Information ◽  
Other Hand ◽  
One Year

I shall not attempt to sum up the conclusions of the day’s discussion, because what conclusions we have come to (and quite a number of points have come out clearly) are rather involved and technical, and I should not at this time go into details; on many major points we have not reached any definite conclusions. There remains much more interesting work to be done; but I should like to comment on a few facts that have come out: In the first place, one is impressed by the amount of information which has been produced in the course of a year. Most of the problems which we have discussed during the day did not exist even as questions one year ago, and it is quite impressive what has been done in this time. We should not complain that all the answers are not available today. Of course, the existence of parity violation is now established beyond any doubt, and an extremely simple feature seems to emerge, though still subject to exact confirmation, in the behaviour of the polarizations, which seems to select fairly heavily between the possible interactions. On the other hand, we have no clear picture yet of the recoil data which might be capable of tying down the possible interactions very closely, or alternatively of showing us that there is something basically wrong with the whole present approach. We should not discount that possibility at the present stage.

scholarly journals The Philosophy of Religion in Nishida Kitarō : 1901-1914

Théologiques ◽  
2013 ◽  
Vol 20 (1-2) ◽  
pp. 39-60 ◽  
Author(s):  
Agustín Jacinto Zavala
Keyword(s):  
Academic Career ◽  
Philosophy Of Religion ◽  
The Other ◽  
Pure Land ◽  
Pure Land Buddhism ◽  
Other Hand ◽  
Early Text ◽  
One Year ◽  
Nishida Kitaro

The Study of Religion (Shūkyō-gaku) is an early text from a one-year course, 1913-1914, which Nishida Kitarō imparted only once in his academic career. In this text, apart from references to mystics and to early and medieval Christian thinkers, Nishida tries to point out the basic elements of Eastern and Western religions through the writings of xviii-xxth century authors, among them participants in the Gifford Lectures, the Bampton Lectures and Hibbert Lectures. On the other hand, Nishida tries to find the corresponding characteristics of religion in Zen and True Pure Land Buddhism. In short, Nishida’s approach to a philosophy of religion gives us an overview of the problems concerning a Buddhist-Christian dialogue.

The Implementation of Data Warehouse Supporting Intuitionistic Fuzzy Data

2011 ◽  
Vol 268-270 ◽  
pp. 1006-1011
Author(s):  
Jun Qing Jiang ◽  
Wei Rui Feng ◽  
Yun Ting Wu
Keyword(s):  
Data Warehouse ◽  
The Other ◽  
Fuzzy Data ◽  
Theoretical Concepts ◽  
Intuitionistic Fuzzy ◽  
Other Hand ◽  
Intuitionistic Fuzzy Data

The multitude of operations over IFS is barely studied empirically. At the other hand they are quite complex and their properties are studied just theoretically. The IFDW that was developed was used to demonstrate the application of some operations over IFSs. It could serve as a basis for implementation of other IFS operations and the data gathered – to explore empirically the validity of the theoretical concepts.

Ausfall der Potenz zur Borstenbildung als „Erbmerkmal“ einer Zellkultur von Drosophila melanogaster

1965 ◽  
Vol 20 (4) ◽  
pp. 290-292 ◽  
Author(s):  
Ernst Hadorn
Keyword(s):  
Drosophila Melanogaster ◽  
Cell Line ◽  
The Other ◽  
Ground Pattern ◽  
Other Hand ◽  
A Cell ◽  
Developmental Factor ◽  
One Year ◽  
Cuticular Structures

The occurrence and the manifestation of a cell line is described which had suddenly and irreversibly lost the potency for forming bristles on any part of the adult cuticle after culturing in vivo over a period of more than one year. On the other hand, it is shown that the cells maintained the capacity for the differentiation of the region-specific ground pattern which consists of hairs and other cuticular structures and which characterize antennae, head parts, legs, wings and the thorax. The aristae are not affected by the change which initiated the bristle-less cell line. Thus it is concluded that the aristae are formations belonging to the ground pattern. A general developmental factor which is indispensible for and common to all bristles regard-less of their organspecific structure is postulated.

The Bolivian puzzle. Why did MAS win the elections again one year after the overthrow?

2021 ◽  
pp. 73
Author(s):  
Alexey Chernyshev
Keyword(s):  
Latin America ◽  
Political Culture ◽  
Social Structure ◽  
The Other ◽  
Andean Region ◽  
Political Situation ◽  
Other Hand ◽  
One Year ◽  
The Moment ◽  
The Right

The Luis Arce’s victory in the elections of the 2020 in Bolivia, on one hand, could be perceived as an unexpected one due to an extremely adverse political situation for the Movement toward the Socialism (Movimiento al Socialismo, MAS), but on the other hand it’s still understandable and attributable to some circumstances of the moment, as well as to some fundamental characteristics of the Bolivian society with its political culture peculiarities, complex social structure and the factor of the indigenous ethnic voting. The indigenous ethnic voting factor seems to gain more importance in the Andean region, if we consider the recent elections in Ecuador and Peru in the 2021. Moreover, the return of the MAS to power in Bolivia shall be analysed within the other regional phenomenon which is the strengthening of the left forces positions, contrary to the mid-2010s forecasts about the “right turn” in the Latin America.

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