ORA-39014 ORA-39029 ORA-31672 One or more workers have prematurely exited

Error Description:
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Whenever you tried to import data into the database it failed with error as below.

Processing object type DATABASE_EXPORT/DE_SYSTEM_PROCOBJACT/DE_PRE_SYSTEM_ACTIONS/PROCACT_SYSTEM
Processing object type DATABASE_EXPORT/DE_SYSTEM_PROCOBJACT/DE_POST_SYSTEM_ACTIONS/PROCACT_SYSTEM
ORA-39014: One or more workers have prematurely exited.
ORA-39029: worker 1 with process name "DW01" prematurely terminated
ORA-31672: Worker process DW01 died unexpectedly.
Job "SYSTEM"."SYS_IMPORT_FULL_03" stopped due to fatal error at 14:13
ORA-39014: One or more workers have prematurely exited.

Cause of The Problem:
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This problem is likely to happen as because of the parallel settings. If you have only 1 dump file in the dump file set and you give PARALLEL parameter to a higher value then this error may occur. The parallelism setting should be less than or equal to the number of dump files in the dump file set.

Solution of The Problem:
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The parallelism setting (specified with the PARALLEL parameter) should be less than or equal to the number of dump files in the dump file set. If there are not enough dump files, the performance will not be optimal because multiple threads of execution will be trying to access the same dump file.

As workaround do import will PARALLEL=1.