Demystifying the Type 2 Slowly Changing Dimension with BIML
Most data warehouses have at least a couple of Type 2 Slowly Changing Dimensions. We use them to keep history so we can see what an entity looked like at the time an event occurred. From an ETL standpoint, I think Type 2 SCDs are the most commonly over-complicated and under-optimized design pattern I encounter. I show the design pattern and the BIML for a Type 2 dimension to demonstrate that they don't have to be difficult.
last updated 12.21.15