
BI Data Quality Investigator
Trace, quantify, and fix data quality issues systematically
What You Can Do
You'll systematically diagnose data quality problems by developing structured root cause analysis frameworks, calculating the true business impact, and creating reproducible validation tests. This skill walks you through hypothesis-driven investigation, data lineage analysis, and remediation planning — turning data issues into documented fixes and preventive measures.
Features
Structured methodology to trace issues from symptom to source with competing hypotheses
Calculate downstream effects and business cost of data quality problems
Create SQL/Python tests that verify fixes and prevent regression
Track data flow across pipelines to identify contamination points
Generate metrics-based health reports by source, table, and dimension
Systematically test competing root causes with evidence
Document fix procedures, verification steps, and stakeholder communication
Example Output
Investigation Summary
- Issue: Revenue dashboard shows $500K discrepancy vs. GL records
- Root cause: Timezone conversion error in ETL pipeline (UTC vs. EST)
- Impact: $500K in unreconciled transactions affecting monthly close
- Validation test: SQL query comparing GL dates before/after conversion
Remediation Playbook
- Apply timezone fix to ETL transformation
- Backfill affected 90-day period using validation query
- Deploy updated pipeline with regression test
- Monitor dashboard reconciliation daily for 2 weeks
Quality Scorecard
| Data Source | Completeness | Timeliness | Accuracy |
|---|---|---|---|
| Billing API | 99.8% | 2h lag | 99.2% |
| GL Extract | 100% | 24h lag | 99.9% |
What's Included
- SKILL.md: Core investigation framework with decision trees and templates
- Root cause analysis template: Structured worksheet for tracing issues
- Data quality validation checklist: Questions to verify each hypothesis
- Impact assessment worksheet: Calculate affected records and business cost
- SQL/Python validation script templates: Ready-to-run quality tests
- Investigation report template: Stakeholder-ready documentation
Who It's For
- Data engineers — Investigating pipeline failures and data contamination
- BI analysts — Troubleshooting dashboard inconsistencies and metric discrepancies
- Data quality managers — Conducting audits and compliance validations
- Analytics leads — Assessing data reliability for critical decision-making
- Database administrators — Investigating data corruption or sync issues
Best For
- Diagnosing unexplained metric discrepancies between systems
- Creating proactive data quality testing frameworks
- Quantifying business impact of data issues for stakeholders
- Building data governance standards and quality SLAs
- Training teams on systematic root cause investigation







