# Design an orders table where one foreign key is required (every order needs a customer) and another

Canonical URL: <https://datadriven.io/problems/design-an-orders-table-where-one-foreign-key-is-required-ev-02436d3f>

Domain: Data Modeling · Difficulty: medium

## Problem

Design an orders table where one foreign key is required (every order needs a customer) and another is optional (a coupon may or may not apply).

## Related

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