# Incremental CDC deltas arrive, but the warehouse table is append-only, so an updated order shows up

Canonical URL: <https://datadriven.io/problems/incremental-cdc-deltas-arrive-but-the-warehouse-table-is-ap-f0c38360>

Domain: Pipeline Design · Difficulty: medium

## Problem

Incremental CDC deltas arrive, but the warehouse table is append-only, so an updated order shows up as two rows and downstream counts are wrong. Design the load so an update replaces the prior version instead of duplicating it.

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