# Put it all together: an intermediate freshness pipeline must merge CDC deltas without duplicates, ve

Canonical URL: <https://datadriven.io/problems/put-it-all-together-an-intermediate-freshness-pipeline-must-521405a6>

Domain: Pipeline Design · Difficulty: medium

## Problem

Put it all together: an intermediate freshness pipeline must merge CDC deltas without duplicates, version dimensions as SCD2, migrate schema online without breaking readers, and backfill corrected partitions idempotently under a quality gate.

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