# A platform team has two transforms wired backwards

Canonical URL: <https://datadriven.io/problems/a-platform-team-has-two-transforms-wired-backwards-a-daily-cb91b87b>

Domain: Pipeline Design · Difficulty: medium

## Problem

A platform team has two transforms wired backwards. A daily 12-table revenue join runs on a $4K/month Spark cluster pulling data out of Snowflake and writing it back; a PyTorch image-feature extraction runs as a dbt SQL UDF that silently writes nulls. Apply the section's ETL-vs-ELT rule and swap the two transforms so each runs on the right tool.

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