# Finance found a rounding bug introduced 30 days ago in daily_revenue

Canonical URL: <https://datadriven.io/problems/finance-found-a-rounding-bug-introduced-30-days-ago-in-daily-d1a43400>

Domain: Pipeline Design · Difficulty: medium

## Problem

Finance found a rounding bug introduced 30 days ago in daily_revenue. Today's run is correct; the last 30 days are off. They need a backward backfill replacing each day's partition. The pipeline reads NOW(), INSERTs into plain Snowflake, and has no orchestrator. Apply the section's four backfill prerequisites so the orchestrator can drive a clean loop over dates.

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