Resumen

MORENO, Francisco  y  ARANGO, Fernando. Operators for reclassification que- queries in a temporal multidimensio- ries multidimensional model. Ing. Investig. [online]. 2011, vol.31, n.1, pp.99-107. ISSN 0120-5609.

Data warehouse dimensions are usually considered to be static because their schema and data tend not to change; however, both dimension schema and dimension data can change. This paper focuses on a type of dimension data change called reclassification which occurs when a member of a certain level becomes a member of a higher level in the same dimension, e.g. when a product changes category (it is reclassified). This type of change gives rise to the notion of classification period and to a type of query that can be useful for decision-support. For example, What were total chess-set sales during first classification period in Toy category? A set of operators has been proposed to facilitate formulating this type of query and it is shown how to incorporate them in SQL, a familiar database developer language. Our operators´ expressivity is also shown because formulating such queries without using these operators usually leads to complex and nonintuitive solutions.

Palabras clave : temporal data warehouse; OLAP; reclassification; classification period.

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