RSS Description:
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There are quite a few ways of ways of documenting the changes a business entity goes through over time. The most famous of them all (and the most difficult to build) is a Slowly Changing Dimension (SCD) type 2. doing this in a table, you would create a table which would include: an incremental key, the business key, the attributes you'd like to track for that entity, a start date and an end date (for which the information was right) and a flag which would equal 1 when we are looking at the last row available for the member of that entity.
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Comments:
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How to implement Slowly Changing Dimensions (type 2 dimensions) in Analysis Services (SSAS).Type 2 and 3 dimensions defines complex real life scenarios: people moving from one departmanet to the other, or changing the working location (moving from one office in a given city to another one...).
Don't think that SSAS will do all the work for you magically, you will need to prepare the DataMart adding a surrogate key, intial date, finish date and a flag (current active), the relations as well will have to be constructed using the surrogate key, ... a lot of fun involved here :-).
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