SQL> select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------- ------------ --------------
1 1 72 52428800 512 2 NO INACTIVE 2508396 28-4月 -14 2549272 05-5月 -14
2 1 73 52428800 512 2 NO CURRENT 2549272 05-5月 -14 2.8147E+14
3 1 71 52428800 512 2 NO INACTIVE 2501657 28-4月 -14 2508396 28-4月 -14

SQL> select * from v$logfile;

GROUP# STATUS TYPE MEMBER IS_
---------- ------- ------- -------------------------------------------------- ---
3 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO03.LOG NO
2 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO02.LOG NO
1 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO01.LOG NO
1 ONLINE E:\ORACLE\DBS\REDO001B.LOG NO
2 ONLINE E:\ORACLE\DBS\REDO002B.LOG NO
3 ONLINE E:\ORACLE\DBS\REDO003B.LOG NO

已选择6行。

-------------------------------------------------------------------------------------------------------------------
before modify, we should backup the database, we omitted here.
-------------------------------------------------------------------------------------------------------------------

SQL> alter database drop logfile member 'E:\ORACLE\DBS\REDO001B.LOG';

数据库已更改。

SQL> alter database drop logfile member 'E:\ORACLE\DBS\REDO003B.LOG';

数据库已更改。

SQL> select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------- ------------ --------------
1 1 72 52428800 512 1 NO INACTIVE 2508396 28-4月 -14 2549272 05-5月 -14
2 1 73 52428800 512 2 NO CURRENT 2549272 05-5月 -14 2.8147E+14
3 1 71 52428800 512 1 NO INACTIVE 2501657 28-4月 -14 2508396 28-4月 -14

SQL> select * from v$logfile;

GROUP# STATUS TYPE MEMBER IS_
---------- ------- ------- -------------------------------------------------- ---
3 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO03.LOG NO
2 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO02.LOG NO
1 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO01.LOG NO
2 ONLINE E:\ORACLE\DBS\REDO002B.LOG NO

SQL> alter system switch logfile;

系统已更改。

SQL> select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------- ------------ --------------
1 1 72 52428800 512 1 NO INACTIVE 2508396 28-4月 -14 2549272 05-5月 -14
2 1 73 52428800 512 2 NO ACTIVE 2549272 05-5月 -14 2552361 05-5月 -14
3 1 74 52428800 512 1 NO CURRENT 2552361 05-5月 -14 2.8147E+14

SQL> alter system switch logfile;

系统已更改。

SQL> select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------- ------------ --------------
1 1 75 52428800 512 1 NO CURRENT 2552377 05-5月 -14 2.8147E+14
2 1 73 52428800 512 2 NO ACTIVE 2549272 05-5月 -14 2552361 05-5月 -14
3 1 74 52428800 512 1 NO ACTIVE 2552361 05-5月 -14 2552377 05-5月 -14

SQL> alter system checkpoint;

系统已更改。

SQL> select * from v$log;

GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------- ------------ --------------
1 1 75 52428800 512 1 NO CURRENT 2552377 05-5月 -14 2.8147E+14
2 1 73 52428800 512 2 NO INACTIVE 2549272 05-5月 -14 2552361 05-5月 -14
3 1 74 52428800 512 1 NO INACTIVE 2552361 05-5月 -14 2552377 05-5月 -14

E:\oracle\dbs>ls -al
total 153607
drwxr-xr-x 2 Administrator Administrators 0 Apr 17 16:35 .
drwxr-xr-x 3 Administrator Administrators 4096 Apr 18 14:33 ..
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:05 REDO001B.LOG
-rw-r--r-- 1 Administrator Administrators 52429312 Apr 28 09:07 REDO002B.LOG
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:05 REDO003B.LOG

SQL> host ls -al E:\oracle\dbs
total 153607
drwxr-xr-x 2 Administrator Administrators 0 Apr 17 16:35 .
drwxr-xr-x 3 Administrator Administrators 4096 Apr 18 14:33 ..
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:05 REDO001B.LOG
-rw-r--r-- 1 Administrator Administrators 52429312 Apr 28 09:07 REDO002B.LOG
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:05 REDO003B.LOG

SQL> select * from v$logfile;

GROUP# STATUS TYPE MEMBER IS_
---------- ------- ------- -------------------------------------------------- ---
3 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO03.LOG NO
2 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO02.LOG NO
1 ONLINE F:\APP\ADMINISTRATOR\ORADATA\ORCL\REDO01.LOG NO
2 ONLINE E:\ORACLE\DBS\REDO002B.LOG NO

SQL> alter database drop logfile member 'E:\ORACLE\DBS\REDO002B.LOG';

数据库已更改。

SQL> host ls -al E:\oracle\dbs
total 153607
drwxr-xr-x 2 Administrator Administrators 0 Apr 17 16:35 .
drwxr-xr-x 3 Administrator Administrators 4096 Apr 18 14:33 ..
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:05 REDO001B.LOG
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:13 REDO002B.LOG
-rw-r--r-- 1 Administrator Administrators 52429312 May 5 15:05 REDO003B.LOG

E:\oracle\dbs>rm -f *.LOG

E:\oracle\dbs>ls -al
total 4
drwxr-xr-x 2 Administrator Administrators 0 May 5 15:14 .
drwxr-xr-x 3 Administrator Administrators 4096 Apr 18 14:33 ..

-------------------------------------------------------------------------------------------------------------------
after modify, we should backup the database, too. we omitted here.
-------------------------------------------------------------------------------------------------------------------