# The section's 90/10 rule: ninety percent of silent failures are caught by ten percent of the possibl

Canonical URL: <https://datadriven.io/problems/the-sections-9010-rule-ninety-percent-of-silent-failures-a629c0d8>

Domain: Pipeline Design · Difficulty: medium

## Problem

The section's 90/10 rule: ninety percent of silent failures are caught by ten percent of the possible checks. The four cheap ones are row count (against a recent baseline), null rate (per column), uniqueness (on the primary key), and freshness (latest record vs current time). They run in seconds, need only basic SQL, and are explainable to a finance partner without a phone call. Pick row count, null, uniqueness, or freshness on the canvas: add four quality-check nodes between the transform and the mart, one per check, each named so the assertion and the threshold or baseline window are visible.

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