Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Quarantine tables** store rows failing validation (schema, business rules, duplicates). Downstream reads only from validated path—ensuring quality. **Flow**: Validate → route pass to main, fail to quarantine. **Schema**: Mirror main + error_code, error_message, reject_reason....
Quarantine tables store rows failing validation (schema, business rules, duplicates). Downstream reads only from validated path—ensuring quality. Flow: Validate → route pass to main, fail to quarantine. Schema: Mirror main + error_code, error_message, reject_reason. Governance: Periodic review; remediate or discard; alert on volume spike. Why: Prevents bad data propagation; traceability for debugging. Cost: Storage for quarantine; ops for review.
Red Flag: Silently dropping failures without quarantine. Pro-Move: 'We had a quarantine dashboard—alert when >1% fail; weekly review found a source schema drift before it hit prod.'
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