Run the failure
Use the red CTA to create the analytical problem intentionally.
Practice Lab · 05 · Data Quality & Validation
Dashboard Trust Incident
A city dashboard says orders collapsed 34%. Inject duplicates, null mappings and stale data, then decide whether to escalate.
FreshnessNull spikesDuplicatesTrust classification
Case brief
Classify the result as business-ready, suspicious, or blocked before telling Operations.
01
Your task
Break it. Run the checks. Explain the evidence.
Predict the result
Before validating, decide what you expect row counts or metrics to do.
Run validation
Use the green CTA to reveal the checks that catch the failure.
Explain it
Say what broke in plain business language, not only SQL language.
02
Interactive case
Run this.
RUN THIS CASE ↓
Dashboard Trust Incident
Classify the result as business-ready, suspicious, or blocked before telling Operations.
Ready — run the case. The headline moves while integrity checks fail.
CheckBaselineCurrentStatus
Rows148,220148,230154,870✓!
Distinct orders148,220148,230✓
Null city_id0.3%0.4%7.8%✓!
Latest event age6 min8 min104 min✓!
The -34% city decline is not trustworthy yet.
QA points to stale data, mapping loss and duplicate-like row growth. Fix integrity first, then rerun the business analysis.
Debrief unlocked
What should the analyst learn?
- Validate the data before explaining the business.
- Freshness, uniqueness and mapping checks belong in first-pass QA.
- Communicate when a number is not decision-ready.
03
Transfer
Use the same checks at work.
Validate the data before explaining the business.
Freshness, uniqueness and mapping checks belong in first-pass QA.
Communicate when a number is not decision-ready.