SQLBits 2020

Slowly Changing Dimensions made Easy with Durable Keys

In this session we look at a simple way to implement Kimball durable keys on a SCD2 dimension. This provides an easy, performant, way to support reporting on data using historical and current hierarchies.

SCD2 dimensions allow us to link fact records to dimensional data as it was at the time the fact was recorded. However, business often want to see the data on a current hierarchy, or at an arbitrary point in time.

This is typically done using business key joins in the dimension, or having two versions of the dimension.

In this talk we look at how we can implement Kimball durable keys on our SCD2 dimensions, providing a simple way to meet the business needs whilst giving great performance.