# Design a layered aggregation system: a detail fact table, daily summary, and monthly summary

Canonical URL: <https://datadriven.io/problems/design-a-layered-aggregation-system-a-detail-fact-table-da-53382589>

Domain: Data Modeling · Difficulty: medium

## Problem

Design a layered aggregation system: a detail fact table, daily summary, and monthly summary. Each layer should support drilling down to the next.

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