修改之前先备份一下，防止出现意外  
create pfile='/home/oracle/0144CISD.ora' from spfile

select group#,thread#,bytes/1024/1024,status from v$log;
 
alter database add logfile thread 1 group 11 '+DATA' size 1G;
alter database add logfile thread 1 group 12 '+DATA' size 1G;
alter database add logfile thread 1 group 13 '+DATA' size 1G;
alter database add logfile thread 1 group 14 '+DATA' size 1G;
alter database add logfile thread 1 group 15 '+DATA' size 1G;
 
 
 
alter database add logfile thread 2 group 16 '+DATA' size 1G;
alter database add logfile thread 2 group 17 '+DATA' size 1G;
alter database add logfile thread 2 group 18 '+DATA' size 1G;
alter database add logfile thread 2 group 19 '+DATA' size 1G;
alter database add logfile thread 2 group 20 '+DATA' size 1G;
 
alter system switch logfile;
 
alter database drop logfile group 1;
alter database drop logfile group 2;
alter database drop logfile group 3;
alter database drop logfile group 4;
alter database drop logfile group 5;
alter database drop logfile group 6;
alter database drop logfile group 7;
alter database drop logfile group 8;
alter database drop logfile group 9;
alter database drop logfile group 10;