If we try to export a dumpfile with the name, which is already present in that directory. then we will get error like ORA-27038: created file already exists

ORA-39001: invalid argument value
ORA-39000: bad dump file specification
ORA-31641: unable to create dump file “/export/home/oracle/dbaclass_estim.dmp
ORA-27038: created file already exists
Additional information: 1

So if the requirement is to overwrite the existing dumpfile, then REUSE_DUMPFILES parameter can be used with EXPDP.

REUSE_DUMPFILES
Overwrite destination dump file if it exists [NO].

DEMO:

PARFILE WITH REUSE_DUMPFILES=Y

At this point, we already have the dumpfile dbaclass_estim.dmp . So the EXPDP job should overwrite this dumpfile.

As expected, we didnt received the error – ORA-27038: created file already exists.