Not Negative Best Practices

Guidelines for getting reliable signal from Not Negative checks while keeping the noise (and the maintenance) low.

Use Not Negative when zero is valid, Positive when it is not

The two rules differ only in how they treat zero. A balance or a stock level of zero is usually legitimate; a quantity or a price of zero usually is not.

Prefer the sign rules over a threshold check for this job

Not Negative states the intent directly and needs no configuration, so it cannot drift out of date the way a numeric threshold can. Reach for Min Value or Between only when the real boundary is a business number rather than the sign.

Pair with Not Null when the value is mandatory

NULL values pass. The rule asserts that present values satisfy it; it does not require the field to be populated. When the field must also have a value, add a Not Null check on the same field.

Keep coverage at 100% unless a known backlog exists

At 100% coverage every failing row is reported as a Record Anomaly, which tells you exactly which values break the rule. Below 100% the check reports a single Shape Anomaly only when the failing fraction crosses the tolerance, and no per-row detail is produced. Lower coverage only while a known set of legacy rows is being cleaned up.

Scope with a filter instead of loosening coverage

When the rule only applies to part of the table (one product line, one tier, one period), express that with a filter clause rather than by lowering coverage. The filter removes the out-of-scope rows from evaluation entirely, and the expression is echoed in every anomaly message.

Route the anomalies to the right people

An out-of-bounds number usually comes from an application that failed to validate its input, or from a unit mismatch upstream. Set an Anomaly Assignee from the team that owns that producer, and tag the check so related checks are easy to find.