However, for a complete import of both schema and data, a permanent fix is required. According to Oracle, this issue was addressed in Oracle Database 20c and later. For customers on older versions, the solution is to apply the interim patch 29450761 . This patch should be available for various platforms and Oracle versions. Before applying it, it is crucial to check for any conflicting patches using the Oracle MOS Patch Planner Tool (Note 1317012.1) to ensure a clean installation.
If patching the database immediately is not an option, use these proven strategic workarounds to complete your data migration: Solution 1: Exclude Problematic Object Types
Before diving into complex fixes, perform these initial steps to isolate the problem:
Certain Oracle patch set updates (PSU) or Release Updates (RU) contain known bugs regarding metadata processing. However, for a complete import of both schema
SELECT * FROM v$pgastat;
impdp system/manager \ DIRECTORY=data_pump_dir \ DUMPFILE=export.dmp \ LOGFILE=debug_imp.log \ TRACE=480300,480301,480302 \ EXCLUDE=STATISTICS \ TABLE_EXISTS_ACTION=REPLACE
Mark leaned back, his coffee cold and his eyes burning, and closed the laptop. The ghost was gone. 🛠️ Key Takeaways for ORA-39126 [71] This patch should be available for various platforms
That will help narrow down whether it's a data corruption, privilege, or bug scenario.
Drop the Master Table associated with the failed job (usually named after the job, e.g., IMPORT_JOB_01 ). 2. Check for Invalid Objects
Issues often arise when importing system-managed schemas (like SYSMAN or SYS ) or when there are character set mismatches between the source and target environments. In this instance
[IMPDP Client] │ ▼ [Master Process (DM00)] ────► Coordinates the job │ ▼ [Worker Process (DW00)] ────► Executes PREPARE_DATA_IMP [71] ──► [CRASH]
Check the Data Pump trace directory for worker trace files ( *dw*.trc ). Look for errors like ORA-01403: no data found , ORA-00942: table or view does not exist , or LPX-00210: expected AS exhibited . Step 2: Verify Database Component Validity
When you see the full message ORA-39126: Worker unexpected fatal error in KUPW$WORKER.PREPARE_DATA_IMP [71] ORA-01403: no data found , the [71] portion is an internal sequence number of the Oracle procedure that failed. In this instance, the primary failure is often accompanied by an ORA-01403: no data found error, which indicates that the Data Pump worker is trying to locate data that does not exist in the expected location.