# Each night a job re-copies the entire 500M-row orders table from the operational DB to the warehouse

Canonical URL: <https://datadriven.io/problems/each-night-a-job-re-copies-the-entire-500m-row-orders-table-4ad9026f>

Domain: Pipeline Design · Difficulty: medium

## Problem

Each night a job re-copies the entire 500M-row orders table from the operational DB to the warehouse, taking hours and hammering production. Only a few thousand rows change daily. Design freshness that moves only what changed.

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