Oracle创建日志文件的语法如下: alter database database_name add logfile[group group_number] (file_name[,file_name[,...]]
Oracle创建日志文件的语法如下:
alter database database_name add logfile[group group_number]
(file_name[,file_name[,...]])[SIZE number][reuse];
语法的说明如下;
group group_number为日志文件指定组的编号
file_name为该组创建日志文件成员
size number指定日志文件成员的大小
reuse如果创建的日志文件成员已经存在,可以使用reuse关键字覆盖已经存在的文件。但是如果该文件不能已经属于其他的日志文件组,否则无法替换。
创建日志文件
创建日志文件,,一般指的是向日志文件中添加日志成员,需要使用alter database ...add logfile member语句。
例如,向日志文件组group 4中添加一个新的日志文件;
alter database add logfile member
'f:\orealcfile\logfile\record.log' to group 4;
我们首先查询数据库中的日志文件组:
SQL> select group#,member from v$logfile;
GROUP# MEMBER
-------------------------------------------------------------------------------
3 D:\ORACLE\ORADATA\ORACLE12C\REDO03.LOG
2 D:\ORACLE\ORADATA\ORACLE12C\REDO02.LOG
1 D:\ORACLE\ORADATA\ORACLE12C\REDO01.LOG
然后向该日志文件组中添加日志文件
SQL> alter database add logfile group 4
(
'f:\\oracledata\logfile\redo1.log',
'f:\oracledata\logfile\redo2.log'
)size 10m;
数据库已更改。
再次查询,我们可以看出在系统的数据库日志文件组多出了4号的数据库文件组
SQL> select group#,member from v$logfile;
GROUP# MEMBER
-------------------------------------------------------------------------------
3 D:\ORACLE\ORADATA\ORACLE12C\REDO03.LOG
2 D:\ORACLE\ORADATA\ORACLE12C\REDO02.LOG
1 D:\ORACLE\ORADATA\ORACLE12C\REDO01.LOG
4 F:\ORACLEDATA\LOGFILE\REDO1.LOG
4 F:\ORACLEDATA\LOGFILE\REDO2.LOG
创建日志文件,把该日志文件添加到日志组4
SQL> alter database add logfile member//为相应的日志增加成员
2 'f:\oracledata\logfile\redo3.log'
3 to group 4;
数据库已更改。
SQL> select group#,member from v$logfile;//系统的数据库日志文件组
GROUP# MEMBER
-------------------------------------------------------------------------------
3 D:\ORACLE\ORADATA\ORACLE12C\REDO03.LOG
2 D:\ORACLE\ORADATA\ORACLE12C\REDO02.LOG
2 D:\ORACLE\ORADATA\ORACLE12C\REDO01.LOG
4 F:\ORACLEDATA\LOGFILE\REDO1.LOG
4 F:\ORACLEDATA\LOGFILE\REDO2.LOG
3 F:\ORACLEDATA\LOGFILE\REDO3.LOG
本文永久更新链接地址:

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