us / as sysdba
SQL*Plus: Release 10.2.0.5.0 - Production on Fri Jun 12 23:14:24 2015
Copyright (c) 1982, 2010, Oracle. All Rights Reserved.
Connected to an idle instance.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 2147483648 bytes
Fixed Size 2097696 bytes
Variable Size 536874464 bytes
Database Buffers 1593835520 bytes
Redo Buffers 14675968 bytes
Database mounted.
SQL> set line 200
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
1 1 397 536870912 1 NO INACTIVE 1294462 03-JUN-15
3 1 399 536870912 1 NO CURRENT 1361682 04-JUN-15
2 1 398 536870912 1 YES INACTIVE 1359647 04-JUN-15
SQL> alter database clear logfile group 1;
alter database clear logfile group 1
*
ERROR at line 1:
ORA-00350: log 1 of instance orcl (thread 1) needs to be archived
ORA-00312: online log 1 thread 1: '/u01/app/oracle/oradata/orcl/redo01.log'
SQL> alter database clear unarchived logfile group 1;
Database altered.
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
1 1 0 536870912 1 YES UNUSED 1294462 03-JUN-15
3 1 399 536870912 1 NO CURRENT 1361682 04-JUN-15
2 1 398 536870912 1 YES INACTIVE 1359647 04-JUN-15
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination /home/oracle
Oldest online log sequence 0
Next log sequence to archive 399
Current log sequence 399
SQL>
此时alert日志的输出如下：
Fri Jun 12 23:20:27 CST 2015
alter database clear logfile group 1
Fri Jun 12 23:20:27 CST 2015
ORA-350 signalled during: alter database clear logfile group 1...
Fri Jun 12 23:22:30 CST 2015
alter database clear unarchived logfile group 1
Fri Jun 12 23:22:31 CST 2015
WARNING! CLEARING REDO LOG WHICH HAS NOT BEEN ARCHIVED. BACKUPS TAKEN
BEFORE 06/04/2015 20:28:30 (CHANGE 1359647) CANNOT BE USED FOR RECOVERY.
Clearing online log 1 of thread 1 sequence number 397
Fri Jun 12 23:22:43 CST 2015
Completed: alter database clear unarchived logfile group 1
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