# Design an append-only order event log

Canonical URL: <https://datadriven.io/problems/design-an-append-only-order-event-log-each-action-on-an-ord-f651c984>

Domain: Data Modeling · Difficulty: medium

## Problem

Design an append-only order event log. Each action on an order (created, paid, shipped, delivered) is a new immutable row. Include the order_id, event_type, event_data, and occurred_at timestamp.

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