What Is Multidimensional Analysis?
Multidimensional analysis uses dimensions and measures to analyse data. To do this using Business Intelligence tools such as Cognos 8 you usually need to first model your data dimensionally.
Dimensions are hierarchies and have one or more levels. What dimensions you define depends on your data and your business model. The user can look at the data at any level – for example Team level will show totals of all the members of that team, at Area level you will see the total for all teams within that area.
Measures are usually quantities such as quantity sold, total revenue and so on. Once a measure is selected in the analysis the measure is aggregated to the level you are analysing at. So if you are analysing at Area level
and you have selected the total revenue as your measure, you would see the total revenue, aggregated to Area level.
Often the data you require will be organised into a data warehouse consisting of dimensional and fact tables and produced by a skilled data warehouse team.
The data is then modelled as metadata and published to make it available for analysis. In Cognos 8 this is achieved using the Framework Manager application. Hierarchies for each dimension are stored in the model so do not need to be defined by the user.
OLAP Data Sources
Sometimes the data source itself is dimensional, for example a SAP B/W cube or a Cognos Powercube. These data sources can be input directly into the Framework model and do not require further modelling.
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