This command directs the Data Pump to write the DDL to a file instead of executing it. It validates the dump file’s structural integrity without loading any data.
, refers to a specific internal line or code path within the KUPW$WORKER
Probable causes (ranked)
Using specific transformations like REMAP_TABLE or REMAP_TABLESPACE combined with tables containing complex data structures (LOBs, partitioned tables, nested collections, or identity columns) can lead to data dictionary mismatches if the target schema already contains a conflicting table skeleton. This command directs the Data Pump to write
:
The worker may fail if it cannot allocate necessary temporary space to manage the master table or metadata. Version Incompatibility:
When importing into a target table with a different definition than the source: : The worker may fail if it cannot
SELECT object_name, status FROM user_datapump_jobs; SELECT * FROM user_load_objects WHERE job_name = 'YOUR_JOB_NAME';
While the ORA-39126 message itself is often high-level, it is almost always accompanied by a second, more descriptive error in the log or trace file, such as ORA-01403: no data found ORA-06502: PL/SQL: numeric or value error Common Root Causes Corrupted Data Pump Metadata: If the internal packages used by Data Pump (like DBMS_METADATA
Attempting to import a dump file from a newer Oracle version into an older database without using the parameter can cause internal worker failures. Invalid Objects in SYS/SYSTEM: PGA configuration limits (like PGA_AGGREGATE_LIMIT ) can be
The worker process can fail if it runs out of Program Global Area (PGA) memory while handling a large or complex object, such as those involving Large Objects (LOBs) or XMLType data. PGA configuration limits (like PGA_AGGREGATE_LIMIT ) can be a primary suspect in many cases. Errors like ORA-01555: snapshot too old can also surface, especially during large imports with significant undo requirements.
If migrating between different OS types or major versions (e.g., 11g Windows to 12c Linux), avoid importing all schemas at once. Explicitly include only your application schemas and exclude system schemas: EXCLUDE=SCHEMA:"IN ('SYSMAN', 'XDB', 'WMSYS')" .