oracle联机重做日志文件(online redo log file)(三)
E MEMBER
---------- ------- --------------------------------------------------
3 ONLINE D:\APP\TOPWQP\ORADATA\ORCL\REDO03.LOG
2 ONLINE D:\APP\TOPWQP\ORADATA\ORCL\REDO02.LOG
1 ONLINE D:\APP\TOPWQP\ORADATA\ORCL\REDO01.LOG
4 ONLINE D:\APP\TOPWQP\ORADATA\ORCL\REDO04.LOG
一个instance 需要 至少两组 online redo log files 文件。
8 ： 删除 redo files groups组
一个active 或者 current 的组不能够删除。
inactive 状态 表示 redo log files中的脏数据已经回写到 数据文件中，
所以是 inactive状态。可以删除改组。
如果你想删除 current 状态的 group 可以通过
alter system switch logfile;
当删除组； 同样这个删除只是在 control file中登记 如果想彻底删除，需要手工用操作系统删除。
alter database drop logfile group 4
命令为： ALTER DATABASE DROP LOGFILE GROUP 4;
[sql]
SQL> select group#,members,archived,status from v$log;
GROUP# MEMBERS ARC STATUS
---------- ---------- --- ----------------
1 1 NO INACTIVE
2 1 NO INACTIVE
3 1 NO CURRENT
4 1 YES UNUSED
SQL> ALTER DATABASE DROP LOGFILE GROUP 4;
数据库已更改。
SQL> select group#,members,archived,status from v$log;
GROUP# MEMBERS ARC STATUS
---------- ---------- --- ----------------
1 1 NO INACTIVE
2 1 NO INACTIVE
3 1 NO CURRENT
9 ： relocate 和 rename
在该redo log file的结构的时候 必须备份数据库。
relocate 之前
1 ： 首先 shutdown immediate
2: ： 到目录下 然后 拷贝，
3： startup mount
4 ： alter database rename file '文件路径文件名' to '文件路径文件名';
参照如下即可：
5. Relocating A redo log Group
You may want to relocate your existing redo log group and change the path of redo log files. Here are the steps to accomplish it
Step 1: Shutdown database
1
sql>
shutdown immediate ;
Step 2: Backup your existing control file and redo log file at operating system level.
Step 3: Move your redo log member to a new location. You may also change the file name if you want.
1
#
mv /u02/oradata/mydb/redo02.log /u03/oradata/mydb/redo03.log
Step 4: Startup in nomount mode
1
sql>
startup nomount;
Step 5: Path of redo log files is kept in control file. You have to update that record by command below:
1
sql>
ALTER
DATABASE
RENAME FILE '/u02/oradata/mydb/redo02.log'
TO
'/u03/oradata/mydb/redo03.log'
Control file is modified and the path of redo log member is updated. Now you can open your database.
1
sql>
alter
database
open;