4. Super-Sub Types — Can a Customer Be Both Individual and Corporate?

Super-sub types clarify business classifications at the logical model level. When converting to a physical model, three options emerge — and in a DW, that choice reshapes the entire dimension design.

February 22, 2026 · 4 min · Junho Lee

3. ERD Notation — Same Diagram, Different Interpretation

Same Crow’s Foot, different meaning. A single dashed line means different things in different tools. If you want models to serve as a shared language on your project, start by aligning on notation.

February 21, 2026 · 4 min · Junho Lee