TABLE_EXISTS_ACTION
option in IMPDP:
TABLE_EXISTS_ACTION
Action to take if imported object already exists.
Valid keywords are: APPEND, REPLACE, [SKIP] and TRUNCATE.
This is the default option with impdp. I.e if the the table exists, it will skip that table.
while importing the table, if the table exists in the database, then it will append the data on top the existing data in the table.
impdp dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=APPEND
While importing the table, if the table exists in database, it will truncate the table and load the data.
impdp dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=TRUNCATE
While importing, if the table exists in database, then it will drop it and recreate it from the dump
impdp dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=REPLACE