Screenshot of the Hierarchy Overlay on a date dimension node. The date node is rendered with a horizontally stacked chain above the column list: four rounded pills connected by right-arrows — "year" → "quarter" → "month" → "day", each pill showing the column name and a small count of distinct values (e.g. "year · 5 values", "quarter · 20", "month · 60", "day · 1 826"). The top of the node has a header label "date — time hierarchy". Behind the overlay the normal column list is visible but slightly dimmed to emphasise the hierarchy. A tooltip on the "month" pill reads "Drill-down from quarter · click-to-drill in any pivot". Dimensions: 1100x600px. Purpose: teach modellers that the hierarchy is explicit, visible, and queryable — not hidden metadata.