Backup Oracle Database

 1. EXPDP

CREATE OR REPLACE DIRECTORY 
EXT_TAB_DIR AS 
'E:\oraclehomeuser\ext_tab_dir\'
/
GRANT READ, WRITE ON DIRECTORY EXT_TAB_DIR TO DBA
/
GRANT READ, WRITE ON DIRECTORY EXT_TAB_DIR TO EXP_FULL_DATABASE
/
GRANT READ, WRITE ON DIRECTORY EXT_TAB_DIR TO IMP_FULL_DATABASE
/
GRANT READ, WRITE ON DIRECTORY EXT_TAB_DIR TO PUBLIC
/
GRANT READ, WRITE ON DIRECTORY EXT_TAB_DIR TO SYSTEM WITH GRANT OPTION
/
expdp system/power@orcl schemas=sep directory=ext_tab_dir dumpfile=SAPMS.dmp reuse_dumpfiles=Y

select 'ALTER TABLE'|| table_name ||' ALLOCATE EXTENT;' from user_tables where segment_created='NO'