Exporting a database

root> su - oracle

root> export ORACLE_SID = ssss

root> sqlplus / as sysdba

note : if the memory is not sufficient we need to execute the following command as a root user at OS level

                root> !mo

                       mount -t tmpfs shmfs -o size=2g /dev/shm

SQL> select name,open_mode from V$database;

SQL> select name from V$tablespace;

SQL> select name from V$datafile.