# A team got burned by duplicate rows from append-only writes and disabled all retries

Canonical URL: <https://datadriven.io/problems/a-team-got-burned-by-duplicate-rows-from-append-only-writes-c07db6cc>

Domain: Pipeline Design · Difficulty: medium

## Problem

A team got burned by duplicate rows from append-only writes and disabled all retries. Now every transient blip pages a human at 3 a.m. who hits 'rerun' manually. The section names this exact mistake (treating the symptom, not the cause) and frames the fix as a two-way contract. Apply both halves of the contract on the canvas.

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