日志文件管理

SQL> alter database add logfile ('/opt/oracle/reod01.log','/opt/oracle/redo02.log') size 50M;
SQL> alter database add logfile group 5 ('/opt/oracle/reod5_01.log','/opt/oracle/redo5_02.log') size 50M;

SQL> select group#,member from v$logfile order by group#;


SQL> alter database add logfile member 
    '/opt/oracle/redo1_03' to group 1,
    '/opt/oracle/redo2_03' to group 2,
    '/opt/oracle/redo3_03' to group 3;

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删除数据字典与控制文件与被删除的重做日志文件相关的信息
SQL> alter database drop logfile member '/opt/oracle/redo.log';

SQL> alter database drop logfile group 4;

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日志切换,检查点
SQL> show parameter lag;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
archive_lag_target                   integer     0  --日志切换间隔时间
client_result_cache_lag              big integer 3000
plsql_ccflags                        string

SQL> show parameter fast_start_mttr_target  --检查点时间间隔
 
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
fast_start_mttr_target               integer     0
SQL> 

SQL> alter database clear logfile group 5; 清除重做日志文件组
SQL> alter database clear unarchived logfile group 5; 清除的重做日志文件组尚未归档使用吃语句

v$Log  从控制文件中获取所有重做日志文件组的基本信息
v$Logfile  重做日志文件及其成员文件的信息
v$Log_History  重做日志文件的历史信息