3)将数据库置于 MOUNT状态

4)执行命令 alter database rename file ‘/directory_name/redo_name1.log ‘ to

‘/directory_name/redo_name2.log ‘;

5)将数据库置于 OPEN状态

b、增加一个新成员，删除旧成员

alter database add logfile member ‘/directory_name/redo_name.log’ to group 2;

alter database drop logfile member ‘/directory_name/redo_name.log’;

alter system switch logfile;