---
title: "Distinguish missing values from numeric zero"
description: "Verify a table renders and filters absent numeric values differently from zero so legitimate zero measurements are not treated as missing data."
canonical_url: "https://vostride.com/agent-library/data-tables/null-and-zero-display.md"
md_url: "https://vostride.com/agent-library/data-tables/null-and-zero-display.md"
content_kind: "recipe"
topic: "data-tables"
---

# Distinguish missing values from numeric zero

Verify a table renders and filters absent numeric values differently from zero so legitimate zero measurements are not treated as missing data.

## Risk

Falsy-value formatting can replace zero with a missing-value dash, and filters can make the same mistake. The fixture contract explicitly differentiates a recorded zero from an absent measurement.

## Fixtures

- A test metrics table contains Zero probe with numeric 0, Missing probe with null, and Positive probe with numeric 7.
- The product displays null as Not measured and zero as 0, with a Missing measurements filter.
- The seed manifest records exact value types and row identifiers independently of rendered labels.

## Steps

1. Open the metrics table and verify Zero probe displays 0, Missing probe displays Not measured, and Positive probe displays 7.
2. Apply Missing measurements and verify only Missing probe remains.
3. Clear that filter and select the product equality filter for value 0; verify only Zero probe remains.
4. Open Zero probe detail and verify its measured value is explicitly zero rather than absent.
5. Return to the unfiltered table and verify all three distinct representations remain correct after reload.

## Expected results

- The zero and null fixture rows have different visible representations as specified.
- The missing-value filter returns only the null record identifier.
- The zero-equality filter and detail value agree on the numeric zero record without including null.

## False-pass traps

- A dash that could mean zero or missing makes the test oracle ambiguous; use the stated display contract.
- A filter chip reading 0 does not prove the result set excluded absent measurements.

## Cleanup

- Delete the three metrics fixtures and clear all metric filters.

## Use with agent-qa

Adapt this test design to your application's acceptance criteria and configured target using the [recipe execution guide](/agent-library/software-factory/turn-a-recipe-into-an-agent-qa-test.md). External fixture setup and non-UI checks require your own supported hooks or test tooling. Validate the authored test, execute it, and inspect the completed evidence; this recipe is not a recorded test result.

## References

- [agent-qa test](/docs/agent-qa/configuration/test.md)
- [agent-qa first test](/docs/agent-qa/guides/first-test.md)
- [agent-qa web testing](/docs/agent-qa/guides/web-testing.md)

- [Data table QA recipes](/agent-library/data-tables.md)
- [Software factory QA library](/agent-library.md)