维护在线redo log

来源：互联网发布：变频器仿真软件下载编辑：程序博客网时间：2024/04/29 20:35
维护在线redo log Oracle Database - Enterprise Edition - Version 11.2.0.4 to 11.2.0.4    1. 首先查看当前redo log的大小:             [oracle@oracle ~]$ sqlplus / as sysdbaOracle Database 10g Enterprise Edition Release 10.2.0.1.0 - 64bit Production   SQL> select group#, bytes, status from v$log;        GROUP#      BYTES STATUS---------- ---------- ----------------         1   52428800 CURRENT         2   52428800 INACTIVE         3   52428800 INACTIVE                            当前redo log 是50M，现在扩展到100M                                                                 2. 查看所有的在线日子组成员                                                                                                SQL> select group#, member from v$logfile;                                                                                               GROUP# MEMBER---------- --------------------------------------------------         3 /oracle/oradata/orcl/redo03.log         2 /oracle/oradata/orcl/redo02.log         1 /oracle/oradata/orcl/redo01.log                                                                                      3. 新增加group# 4/5/6大小为100M的redolog                                                          SQL> alter database add logfile group 4                                         '/oracle/oradata/orcl/log4PROD.dbf' size 100M;                                                                     SQL> alter database add logfile group 5                                             '/oracle/oradata/orcl/log5PROD.dbf' size 100M;                SQL> alter database add logfile group 6                     '/oracle/oradata/orcl/log6PROD.dbf' size 100M;           4. 查询当前所有redo log的状态:                                                                                                               SQL> select group#, status from v$log;                                             GROUP# STATUS---------- ----------------         1 CURRENT         2 INACTIVE         3 INACTIVE         4 UNUSED         5 UNUSED         6 UNUSED               当前redolog状态，group 1是当前的在线日志组，group2、3为inactive，我们要删除的是50M的group 1、2、3   group 1 是当前在线日志组，不可以删除，目前可以删除inactive的group 2、3      SQL> alter database drop logfile group 2;        Database altered.                                  SQL> alter database drop logfile group 3;      Database altered.      5. 多次switch log切换日志,直至group 1为inactive状态，:                                      SQL> alter system checkpoint;     System altered.     SQL> alter system switch logfile;    System altered.   SQL> select group#, status from v$log;                                             GROUP# STATUS---------- ----------------         1 INACTIVE         4 UNUSED         5 UNUSED         6 UNUSED            SQL> alter database drop logfile group 1;        Database altered.          注:如果checkpoint，还是不能切换到inactive，那就做几次全局checkpoint    SQL> alter system checkpoint global;    System altered                                                             6.再次查看在线日志所有状态:                                                                                                                            SQL> select group#, bytes, status from v$log;    GROUP#      BYTES STATUS---------- ---------- ----------------         4  104857600 INACTIVE         5  104857600 CURRENT         6  104857600 UNUSED    9.  操作系统层面删除旧的redolog    [oracle@oracle orcl]$rm /oracle/oradata/orcl/redo01.log[oracle@oracle orcl]$rm /oracle/oradata/orcl/redo02.log  [oracle@oracle orcl]$rm /oracle/oradata/orcl/redo03.log                                                                                                  10.删除redo log 最好做一次数据库的备份，维护reodlog的时候最好在业务低峰的时候操作
0 0