How to add,delete group.
If log file have big file size. and want to resize.
can use this step to create new redolog with new size.
Use command for view log group. and command for view status Archive log mode.
SQL > archive log list;
SQL > select * from v$log;
Add log file group
SQL > alter database add log file group 3 ('/u01/database/log03a.dbf','/u01/database/log03b.dbf') size 67M;
If exiting log file has bigsize. you can delete by use this step
SQL > select * from v$log;
** Find log group status "INACTIVE"
and delete log group status "INACTIVE" only.
Assume: log group 1 status is "inactive"
SQL > alter database drop logfile group 1;
and then delete logfile '/u01/database/log01a.dbf' and '/u01/database/log01b.dbf' from OS
You can turn active log group by using command :
SQL > alter system switch logfile;