# Design a One Big Table (OBT) for a marketing dashboard

Canonical URL: <https://datadriven.io/problems/design-a-one-big-table-obt-for-a-marketing-dashboard-flat-afced22b>

Domain: Data Modeling · Difficulty: medium

## Problem

Design a One Big Table (OBT) for a marketing dashboard. Flatten customer, order, and product data into a single wide denormalized table that powers fast analytical queries without joins.

## Related

- [All practice problems](https://datadriven.io/problems)
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