Slowly Changing Dimension (SCD) is great for tracking historical changes to dimension attributes. SCDs have evolved over the years and besides the conventional type 1 (update), type 2 (add row) and type 3 (add column), now there are extensions up to type 7 including type 0. Almost every DW/BI project has at least few type 2 dimensions where a change to an attribute causes the current dimension record to be end dated and creates a new record with the new value.

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