# A daily Python ETL pulls 250,000 orders and INSERTs them into a plain Snowflake table

Canonical URL: <https://datadriven.io/problems/a-daily-python-etl-pulls-250000-orders-and-inserts-them-int-ffe1eec8>

Domain: Pipeline Design · Difficulty: medium

## Problem

A daily Python ETL pulls 250,000 orders and INSERTs them into a plain Snowflake table. Last Tuesday the job crashed at row 180,001; on retry it appended all 250,000 again, leaving 430,000 rows and inflating revenue 41 percent. The section names this the append-plus-retry antipattern. Apply the structural fix: change how the destination writes so retries produce identical state.

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