SQL> alter database drop logfile group 5;
Database altered
SQL> select group#, sequence#, bytes, members, status from v$log;
GROUP# SEQUENCE# BYTES MEMBERS STATUS
---------- ---------- ---------- ---------- ----------------
1 217 52428800 2 INACTIVE
2 218 52428800 2 INACTIVE
3 221 52428800 2 CURRENT
4 219 10485760 2 INACTIVE
ü增加redo log group member
直接增加日志组成员的使用几率相对较少，我们一般是一次性直接将成员文件添加完毕。
SQL> alter database add logfile member '/u01/oradata/WILSON/onlinelog/redo4c.log' to group 4;
Database altered
SQL> select group#, member from v$logfile;
GROUP# MEMBER
-- ----------------------------------------------------------------
3 /u01/oradata/WILSON/onlinelog/o1_mf_3_6bcsqtfj_.log
3 /u01/flash_recovery_area/WILSON/onlinelog/o1_mf_3_6bcsqtwv_.log
2 /u01/oradata/WILSON/onlinelog/o1_mf_2_6bcsqs3t_.log
2 /u01/flash_recovery_area/WILSON/onlinelog/o1_mf_2_6bcsqstm_.log
1 /u01/oradata/WILSON/onlinelog/o1_mf_1_6bcsqpty_.log
1 /u01/flash_recovery_area/WILSON/onlinelog/o1_mf_1_6bcsqqt0_.log
4 /u01/oradata/WILSON/onlinelog/redo4a.log
4 /u01/flash_recovery_area/WILSON/onlinelog/redo4b.log
4 /u01/oradata/WILSON/onlinelog/redo4c.log
9 rows selected
ü删除redo log group member
删除group member.