Topic

#data-modeling

Illustrated overview of Slowly Changing Dimensions: Types 1 Through 6, and the Two You Will Actually Use

Data Modeling

May 18, 202613 min read

Slowly Changing Dimensions: Types 1 Through 6, and the Two You Will Actually Use

Working SQL for every SCD type, the point-in-time join that most Type 2 implementations get wrong, and an honest account of which types are worth the maintenance.

data-modeling
sql

Data Modeling

May 15, 202612 min read

Star Schema vs One Big Table: What Actually Costs Money on a Columnar Warehouse

Joins are not the expense they were in 2015. Here is what a wide denormalized table really costs in storage, rebuild time, and history, and the hybrid I ship instead of picking a side.

data-modeling
sql