lob performance

http://www.ixora.com.au/tips/event_10359.htm
http://download.oracle.com/docs/cd/A91202_01/901_doc/appdev.901/a88879/adl09be3.htm#121892

lob nologging

alter table test_lob modify lob (sql_text) (nocache nologging);

Lost of system datafile

Instance crashes with error: ORA-01243: system tablespace file suffered media failure

Restore to different location:
rman
startup mount;
run
{
set newname for datafile 'f:\test_system.dbf' to 'c:\project\orcl\test_system.dbf';
restore datafile 11;
switch datafile 11;
recover datafile 11;
}

AWR: transfer to other db

dbms_swrf_internal
AWR_EXTRACT -> AWR_LOAD -> MOVE_TO_AWR

asmcmd: ASMCMD-08103: failed to connect to ASM; ASMCMD running in non-connected mode

Can be if any issue with connection to +ASM
try sqlplus / as sysdba

rman: RMAN-10015: error compiling PL/SQL program

RMAN> sql "alter database datafile '/u01/app/oracle/oradata/orcl/test_1.dbf' off line";

using target database control file instead of recovery catalog
sql statement: alter database datafile '/u01/app/oracle/oradata/orcl/test_1.dbf' offline
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of sql command on default channel at 09/06/2010 13:18:57
RMAN-10015: error compiling PL/SQL program

SQL> alter database datafile '/u01/app/oracle/oradata/orcl/test_1.dbf' offline;
alter database datafile '/u01/app/oracle/oradata/orcl/test_1.dbf' offline
*
ERROR at line 1:
ORA-01145: offline immediate disallowed unless media recovery enabled

ASM: adding diskgroup

SQL> alter diskgroup data add disk '/dev/raw/raw2' size 1019m;
alter diskgroup data add disk '/dev/raw/raw2' size 1019m
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15033: disk '/dev/raw/raw2' belongs to diskgroup "DATA"

SQL> a force
1* alter diskgroup data add disk '/dev/raw/raw2' size 1019m force
SQL> /

Diskgroup altered.