# The day-one monitors cover freshness and volume but leave three blind spots

Canonical URL: <https://datadriven.io/problems/the-day-one-monitors-cover-freshness-and-volume-but-leave-th-3c621f3d>

Domain: Pipeline Design · Difficulty: medium

## Problem

The day-one monitors cover freshness and volume but leave three blind spots. The section's framework adds schema (column added, dropped, retyped upstream), distribution (mean shift, null rate spike, new categorical value), and lineage (which downstream consumers does this break). Together the five pillars turn a single-pipeline view into a fleet-level view. Map signals to the five pillars by adding five monitor transforms on the curated table fct_orders, one per pillar, each with a tech that fits the pillar's check, and route the lineage pillar through a catalog node that captures column-to-column provenance.

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