Troubleshooting ORA-01555 - Snapshot Too Old: Rollback Segment Number "String" With Name "String" Too Small (Doc ID 1580790.1) https://support.oracle.com/epmos/faces/DocContentDisplay?id=1580790.1 In this Document Purpose Troubleshooting Steps 1) Check Error Messages: a) Identify segment name: 1. LOB segment corruption: 2. If no LOB corruption found, so Issues with Retention/Pctversion values : b) Identify Query Duration: 2) Check Undo Datafiles : 3) TUNED_UNDORETENTION : 4) High utilization of ACTIVE/UNEXPIRED extents : 5) UNDO_RETENTION : 6) 1555 error during export : 7) How to find the complete SQL statement caused ORA-1555 : APPLIES TO: Oracle Database Cloud Schema Service - Version N/A and later Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later Oracle Database Exadata Express Cloud Service - Version N/A and later Oracle Cloud Infrastructure - Database Ser...
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