KB article
A Context Test Harness for Power BI Models
A test harness validates that key questions return stable results.
arf-kbcontext-stabilitycontext-test-harnessdeterministic-querycontext-volatility
TL;DR
- Define representative queries and expected outcomes.
- Use them to detect context regressions.
The problem
- Context issues are hard to detect until users complain.
- Model changes can silently break answers.
Why it matters
- Tests provide early warning for instability.
- They enable safe iteration on the model.
Symptoms
- Unexpected changes in KPI values after model updates.
- AI answers that drift without data changes.
Root causes
- No regression tests for filter context.
- Model updates lack validation checks.
What good looks like
- A small set of representative queries with expected ranges.
- Regular test runs before deployment.
How to fix
- Define 10–20 representative questions.
- Capture expected outcomes or ranges.
- Run tests after every model change.
Pitfalls
- Testing too many edge cases and ignoring core KPIs.
- Using stale expected values.
Checklist
- Test harness defined and documented.
- Tests run on every release.
- Failures reviewed and resolved.
Framework placement
Primary ARF layer: Context Stability. Diagnostic bridge: data-movement-reliability, semantic-reliability, execution-reliability.