TABLE_EXISTS_ACTION parameter is required while importing table, which is already present in the database. We can put required value, according to our requirement.
TABLE_EXISTS_ACTION
Action to take if imported object already exists.
Valid keywords are: APPEND, REPLACE, [SKIP] and TRUNCATE.
TABLE_EXISTS_ACTION=APPEND:
With this option, 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.
select count(*) from "DBATEST"."EMP_TAB";
COUNT(*)
----------
175340
impdp dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=APPEND
Starting "SYS"."SYS_IMPORT_FULL_01": /******** AS SYSDBA dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=APPEND
Processing object type TABLE_EXPORT/TABLE/TABLE
Table "DBATEST"."EMP_TAB" exists. Data will be appended to existing table but all dependent metadata will be skipped due to table_exists_action of append
Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
. . imported "DBATEST"."EMP_TAB" 19.16 MB 175340 rows
Job "SYS"."SYS_IMPORT_FULL_01" successfully completed at Tue Jan 24 08:57:09 2017 elapsed 0 00:01:18
SQL[SYS@]SQL>>]select count(*) from "DBATEST"."EMP_TAB";
COUNT(*)
----------
350680
TABLE_EXISTS_ACTION=TRUNCATE:
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 Starting "SYS"."SYS_IMPORT_FULL_01": /******** AS SYSDBA dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=TRUNCATE Processing object type TABLE_EXPORT/TABLE/TABLE Table "DBATEST"."EMP_TAB" exists and has been truncated. Data will be loaded but all dependent metadata will be skipped due to table_exists_action of truncate Processing object type TABLE_EXPORT/TABLE/TABLE_DATA . . imported "DBATEST"."EMP_TAB" 19.16 MB 175340 rows Job "SYS"."SYS_IMPORT_FULL_01" successfully completed at Tue Jan 24 09:02:23 2017 elapsed 0 00:01:11
TABLE_EXISTS_ACTION=REPLACE:
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 Starting "SYS"."SYS_IMPORT_FULL_01": /******** AS SYSDBA dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN table_exists_action=REPLACE Processing object type TABLE_EXPORT/TABLE/TABLE Processing object type TABLE_EXPORT/TABLE/TABLE_DATA . . imported "DBATEST"."EMP_TAB" 19.16 MB 175340 rows Job "SYS"."SYS_IMPORT_FULL_01" successfully completed at Tue Jan 24 09:20:30 2017 elapsed 0 00:01:37
TABLE_EXISTS_ACTION=SKIP:
This is the defult option with impdp. I.e if the the table exists, it will skip that table.
Starting "SYS"."SYS_IMPORT_FULL_01": /******** AS SYSDBA dumpfile=emp_tab.dmp logfile=emp_tab.log directory=VEN Processing object type TABLE_EXPORT/TABLE/TABLE ORA-39151: Table "DBATEST"."EMP_TAB" exists. All dependent metadata and data will be skipped due to table_exists_action of skip Processing object type TABLE_EXPORT/TABLE/TABLE_DATA Job "SYS"."SYS_IMPORT_FULL_01" completed with 1 error(s) at Tue Jan 24 09:31:51 2017 elapsed 0 00:01:01
Richard