Some important queries.........!

select open_mode from v$database;
select log_mode from v$database;
select name from v$datafile;
select count(*) from v$datafile;

select name from v$tablespace;
select count(*) from v$tablespace;


Bakup

sql> alter tablespace HRD begin backup ;
copy the datafile to the backup location
sql> alter tablespace HRD end backup;

sql> select open_mode from v$datafile;

sql> alter database open reset logs;



Tablespace Offline:

sql> alter database datafile '/u01/appsmode/jet/oradata/data/HRD01.dbf' offline;

exit
copy the datafile from backup

recover datafile 7;

sql> alter database datafile '/u01/appsmode1/jet/oradata/data/hrd01.dbf' online;

Regards,

Sukhwinder Singh

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