Freshness Anomaly Reporting¶
How the Freshness check reports data that is older than its Maximum Age: what the Shape Anomaly tells you, how to read it, and why there is nothing to report per row.
Anomaly Messages¶
Freshness emits a Shape Anomaly only, one per failed evaluation. The message names the container, how long ago it was last updated, and the Maximum Age it exceeded:
| What failed | Message |
|---|---|
| The last modification is older than the Maximum Age | customers_snapshot was last updated 1 day, 2 hours and 14 minutes ago, longer than the permitted 6 hours |
Durations are written in words, from weeks down to milliseconds, with every unit that is not zero. The age is measured to the millisecond, so the observed age often carries seconds or milliseconds that the Maximum Age does not.
What the Numbers Mean¶
- Observed age: the time between the Scan's reading and the container's last modification time. See Where the Last Modification Time Comes From.
- Permitted age: the check's Maximum Age.
The check fails only when the observed age exceeds the Maximum Age by more than a small margin (up to one minute). See Maximum Age.
When No Anomaly Is Created¶
The check reports nothing, and is recorded as Not Asserted for that Scan, when the container cannot provide a last modification time: for example, a view without an incremental field, or a partitioned Parquet folder.
A day without a Scan never produces an anomaly, even when the Observability chart shows data older than the Maximum Age.
Source Records Behavior¶
Freshness does not evaluate rows, so the anomaly carries no source records. The evidence is the container's modification history, available on its Observability chart. From the check form, the View Freshness chart button opens it directly.
Custom Anomaly Description¶
The form does not offer Custom Anomaly Description for this rule. The option replaces the message on Record Anomalies, and Freshness has no field to select and emits a Shape Anomaly only, so the message is always the fixed one above.
See Also¶
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Examples
Three production scenarios: an extract that stops arriving, a daily load that runs late, and a view measured by its timestamp field.
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Best Practices
Guidelines for scheduling the Scan, setting the Maximum Age, giving views an incremental field, and working with AI Managed checks.
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Permissions
The team permission each action needs: view, create, edit, archive, restore, and delete.
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How It Works
The complete reference: definition, when the check is evaluated, where the last modification time comes from, the Maximum Age, and AI Managed Freshness checks.