Mastering Enterprise BI: Time Intelligence Pt. I By William Pearson

The Time dimension has several unique characteristics, relative to other dimensions within our cube models. Among these is the fact that all businesses employ the same core calendar time hierarchy of days (and sometimes lower levels), weeks, and months, together with quarters and years (with various subdivisions included to meet local business and reporting needs) - even though treatment of these various levels can vary widely within the alternative considerations of fiscal years and periods. Moreover, the pervasive nature of time - within and surrounding all organizational activity - means the universal juxtaposition of the Time dimension and the other dimensions within our cube models. Another characteristic of time is its incremental continuation, like a ray in geometry, from a fixed beginning to a typically indefinite end.

The Time dimension has received special focus within the design of enterprise business intelligence applications. Common features include capabilities ranging from the recognition of date fields with minimal intervention to the automatic generation of members of the Calendar time dimension as a part of cube design and / or creation. Most of the dominant applications have even offered support for the dynamic creation of various “relative” time periods and aggregations. (For a discussion of some of the specific support provided by leading applications, as well as the Analysis Services 2005 approach to meeting and exceeding these features, see other articles within my Introduction to SQL Server 2000 Analysis Services series here at Database Journal).

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