如何调整Oracle Redo Logfile日志文件的大小

折腾日志文件，调整了一下大小，将每个日志文件调整为2G，扩展名取为dbf。
约略记录一下步骤。

在用的是不能删除的：

SQL> col member for a30
SQL> select * from v$logfile;

    GROUP# STATUS  TYPE    MEMBER                         IS_
---------- ------- ------- ------------------------------ ---
         1         ONLINE  /data1/dbstat/redo01.dbf       NO
         3 STALE   ONLINE  /data1/dbstat/redo3.log        NO
         2         ONLINE  /data1/dbstat/redo2.log        NO

SQL> alter database drop logfile group 2;
alter database drop logfile group 2
*
ERROR at line 1:
ORA-01623: log 2 is current log for instance dbstat (thread 1) - cannot drop
ORA-00312: online log 2 thread 1: '/data1/dbstat/redo2.log'

Inactive的删除后，增加新的日志文件：

SQL> alter database drop logfile group 3;

Database altered.

SQL> alter database add logfile group 3 ('/data1/dbstat/redo03.dbf') size 2048M reuse;

Database altered.

SQL> select * from v$logfile;

    GROUP# STATUS  TYPE    MEMBER                         IS_
---------- ------- ------- ------------------------------ ---
         1         ONLINE  /data1/dbstat/redo01.dbf       NO
         3         ONLINE  /data1/dbstat/redo03.dbf       NO
         2         ONLINE  /data1/dbstat/redo2.log        NO

SQL> set linesize 120
SQL> select * from v$Log;

    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
         1          1          0 2147483648          1 YES UNUSED                       0
         2          1         11   52428800          1 NO  CURRENT                 203206 2009-09-17 18:56:08
         3          1          0 2147483648          1 YES UNUSED                       0

切换日志组，当CURRENT变为非活动时（INACTIVE）将其删除：

SQL> alter system switch logfile;

System altered.

SQL> alter database drop logfile group 2;
alter database drop logfile group 2
*
ERROR at line 1:
ORA-01624: log 2 needed for crash recovery of instance dbstat (thread 1)
ORA-00312: online log 2 thread 1: '/data1/dbstat/redo2.log'


SQL> alter system switch logfile;

System altered.

SQL> select * from v$Log;

    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
         1          1         12 2147483648          1 NO  ACTIVE                  203704 2009-09-17 19:04:23
         2          1         11   52428800          1 NO  ACTIVE                  203206 2009-09-17 18:56:08
         3          1         13 2147483648          1 NO  CURRENT                 203710 2009-09-17 19:04:38

SQL> alter system checkpoint;

System altered.

SQL> select * from v$Log;

    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
         1          1         12 2147483648          1 NO  INACTIVE                203704 2009-09-17 19:04:23
         2          1         11   52428800          1 NO  INACTIVE                203206 2009-09-17 18:56:08
         3          1         13 2147483648          1 NO  CURRENT                 203710 2009-09-17 19:04:38

SQL> alter database drop logfile group 2;

Database altered.

SQL> alter database add logfile group 2 ('/data1/dbstat/redo02.dbf') size 2048M;

Database altered.

SQL> select * from v$log;

    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIME
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------
         1          1         12 2147483648          1 NO  INACTIVE                203704 2009-09-17 19:04:23
         2          1          0 2147483648          1 YES UNUSED                       0
         3          1         13 2147483648          1 NO  CURRENT                 203710 2009-09-17 19:04:38

现在就可以应对大规模的日志操作了。

-The End-