ORACLE OMF介绍
先看Oracle 官方解释
Oracle managed file (OMF)
A file that is created automatically by the Oracle database server when it is needed and automatically deleted when it is no longer needed.
如何判断你的数据库是否为支持OMF
SQL> show parameter db_create_file_dest;
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
db_create_file_dest string
如果Value 为空则不支持，有值则支持。
如何设置DB 支持？
修改初始化参数文件
[oracle@itc-test9 dbs]more initOCM.ora
.......
*.user_dump_dest='/disk/oracle/admin/OCM/udump'
db_create_file_dest = '/disk/oracle/oradata'
使用 ALTER SYSTEM 命令动态设置
SQL> alter system set db_create_file_dest='/disk/oracle/oradata ;
System altered.
OMF有些用呢？
我大体总结一个一下就下面几点：
1： 创建Tablespace 是不需要写数据文件名称和大小 （default 100M,自动增长，Autoextend 为unlimited)
SQL> create tablespace omf;
Tablespace created.
Os:
[oracle@itc-test9 datafile]pwd
/disk/oracle/oradata/OCM/datafile
[oracle@itc-test9 datafile]ll
total 102512
-rw-r----- 1 oracle dba 104865792 Apr 29 16:13 o1_mf_omf_4zj30b2p_.dbf
创建数据文件属性：
Name /disk/oracle/oradata/OCM/datafile/o1_mf_omf_4zj30b2p_.dbf
Tablespace OMF
Status Online
File Size (KB) 102400
AutoExtend Yes
Increment 100MB
Maximum File Size 32767MB
2: 向Tablespace 添加文件是只适用add datafile 就可以了，参数如1.
SQL> alter tablespace omf add datafile;
Tablespace altered.
Os
[oracle@itc-test9 datafi
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