Ora-39126 Worker Unexpected Fatal Error In Kupw-worker.prepare-data-imp 71 | 90% WORKING |

: The internal packages or views used by Data Pump may be invalid or corrupted. Missing or Incorrect Tablespaces

This error typically occurs during the phase ( impdp ), specifically when the Data Pump worker process is preparing to load data into a table. The error is a "wrapper" or "umbrella" error—meaning it signals a fatal failure, but the root cause is often hidden in a secondary error stack or requires deep investigation.

You can manually gather statistics using DBMS_STATS.GATHER_SCHEMA_STATS after the import finishes. : The internal packages or views used by

The KUPW$WORKER process is the core engine of Oracle Data Pump, responsible for orchestrating the export and import of database objects. When the worker dies from an unhandled exception, Oracle raises this error. While the main job may continue, any objects being processed by the failed worker will be incomplete or skipped altogether. Pinpointing the root cause is critical, as the error itself is a generic symptom of a variety of underlying problems.

Oracle Data Pump is the backbone of modern Oracle database migrations, backups, and ETL processes. It is praised for its speed, parallelism, and fine-grained object control. However, when it fails, it often fails cryptically. Among the most dreaded errors encountered by database administrators (DBAs) is: You can manually gather statistics using DBMS_STATS

If you are in the middle of a migration, I can help you tailor the impdp command to skip the problematic objects. Please let me know if this is a or full-database import. Share public link

When you initiate an impdp job, a Master Process ( DM00 ) coordinates the operation and assigns metadata and data objects to one or more Worker Processes ( DW00 ). The PL/SQL package code inside SYS.KUPW$WORKER defines the worker's operational steps. While the main job may continue, any objects

Before implementing a fix, a thorough diagnosis is recommended. Follow this structured approach to gather necessary information:

often points to an issue during the initialization phase where the worker is preparing for data import. Oracle Communities Potential Causes Corrupted Data Pump Metadata

Then import that table separately with additional diagnostic parameters: