Ora-39126 Worker Unexpected Fatal Error In Kupw-worker.prepare-data-imp 71 [patched] Link

To resolve the ORA-39126 error, follow these troubleshooting steps:

The Oracle Data Pump suite ( expdp and impdp ) is a powerful tool for high-performance data and metadata movement. However, even the most robust tools can encounter cryptic errors. Among the most frustrating for database administrators (DBAs) and developers is the .

Standard practice is to perform imports using a user with the DATAPUMP_IMP_FULL_DATABASE role (like SYSTEM ) rather than using the AS SYSDBA connection, which can cause unexpected behavior in worker processes. To resolve the ORA-39126 error, follow these troubleshooting

If in a Multitenant environment (CDB/PDB), ensure you run this in the specific PDB that is causing issues. Solution B: Exclude Statistics ( EXCLUDE=STATISTICS )

Before importing the failing table, manually create it with more forgiving attributes: Standard practice is to perform imports using a

Migrating across major Oracle versions (e.g., extracting from 19c and importing into 23ai or 12c) forces Data Pump to convert metadata types. If the original expdp command skipped the VERSION parameter, the dump file structures can trigger code boundaries within the target worker module. 2. Corrupted or Desynchronized Data Pump Catalogs

This error indicates that a Data Pump worker process failed during the data preparation phase of an import operation, often pointing to an internal error or a data consistency issue rather than a simple syntax error. 1. Understanding the Error Structure If the original expdp command skipped the VERSION

The ORA-39126 error is not a single issue but a symptom of many potential problems. The official Oracle documentation defines it as an internal error, but in practice, the root causes often fall into the following categories: