Arthur let out a breath he didn’t know he was holding. It wasn’t corruption. It wasn't a hardware failure. The worker process— KUPW$WORKER —had tried to prepare a chunk of data for import, hit a wall, and threw its hands up in a "fatal error."
When ORA-39126 appears, the worker process usually stacks additional errors. You must look the ORA-39126 line in the log.
By systematically applying the diagnostic and resolution techniques outlined in this article, you can successfully mitigate ORA-39126 and restore full functionality to your Oracle Data Pump operations. Remember, when in doubt, Oracle Support is your final authority for backported patches and deep kernel analysis.
If in a Multitenant environment (CDB/PDB), ensure you run this in the specific PDB that is causing issues. Solution B: Exclude Statistics ( EXCLUDE=STATISTICS ) Arthur let out a breath he didn’t know he was holding
Metadata Inconsistencies: Corrupt or orphaned entries in the database dictionary.Database Bugs: Specific Oracle versions (especially 12c and 19c) have known bugs related to partitioned tables or XMLType columns during import.Invalid Objects: A high number of invalid objects in the SYS or SYSTEM schemas.Insufficient Resource Quotas: The worker fails when trying to create temporary structures or system-level objects.Character Set Mismatches: Issues translating metadata between the source and target database character sets. Troubleshooting Steps
Apply the latest or upgrade to a stable version:
Repeated imports into the same schema without proper cleanup can corrupt the target’s metadata state. The worker process— KUPW$WORKER —had tried to prepare
The error is often triggered by metadata inconsistencies or stale environmental statistics rather than a direct issue with the data itself.
impdp ... CONTENT=DATA_ONLY
impdp user/pwd DIRECTORY=dp_dir DUMPFILE=exp.dmp LOGFILE=imp.log TRACE=480300 Remember, when in doubt, Oracle Support is your
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 .
: cd $ORACLE_HOME/rdbms/admin Execute as SYSDBA : SQL> @dpload.sql Use code with caution. Copied to clipboard
If the dump file was transferred via FTP:
impdp user/password directory=DIR full=y EXCLUDE=SCHEMA:\"IN \(\'SYS\',\'SYSTEM\',\'SYSMAN\'\)\" Use code with caution. Solution 4: Re-export the Data