Advanced concepts

Descriptive attributes
It is often necessary to give additional information on a dimensional attribute in a hierarchy, although it may not be meaningful to use this information as...
Fri, 28 Nov, 2014 at 12:45 AM
Cross-dimensional attributes
A cross-dimensional attribute is a dimensional or descriptive attribute whose value is defined by the combination of two or more dimensional attributes...
Fri, 28 Nov, 2014 at 12:45 AM
Convergences
In a convergence, two or more distinct paths of dimensional attributes within the same hierarchy functionally determine the same dimensional attri...
Fri, 28 Nov, 2014 at 12:46 AM
Shared hierarchies
Entire portions of hierarchies are frequently replicated two or more times in fact schemata. Temporal and geographical hierarchies are classic examples. ...
Fri, 28 Nov, 2014 at 12:46 AM
Multiple arcs
Hierarchies most commonly include attributes connected to their parents by to-one associations. However, it may be necessary to also include attributes th...
Fri, 28 Nov, 2014 at 12:46 AM
Optional arcs
Optionality is used to model scenarios for which an association represented in a fact schema is not defined for a subset of events. For insta...
Fri, 28 Nov, 2014 at 12:46 AM
Incomplete hierarchies
An incomplete hierarchy is one in which one or more levels of aggregation are missing in some instances (because they are not known or defined). ...
Fri, 28 Nov, 2014 at 12:48 AM
Recursive hierarchies
In a recursive hierarchy, the parent-child relationships among the levels are consistent in semantic terms, but hierarchy instances can have any length...
Fri, 28 Nov, 2014 at 12:48 AM