ITPub博客

首页 > 数据库 > Oracle > v$logfile与v$log的STATUS

v$logfile与v$log的STATUS

原创 Oracle 作者:lvqf 时间:2011-04-29 16:12:59 0 删除 编辑

1.v$logfile,描述重做日志文件的信息。其中状态STATUS有:

INVALID - File is inaccessible

STALE - File's contents are incomplete. If the redo log file group member has never been used, either due to a new redo log file group or a repaired member, the value of STATUS is STALE until the log file member is used to record redo information.(如果该重做日志文件成员从未被用过,则它可能是新增加的或是已修复的重做日志文件。这种状态直到它被用于记录重做信息为止。)

[@more@]

DELETED - File is no longer used

null - File is in use(在用的重做日志文件)

2.v$log的信息来自于control file,描述联机重做日志组的当前信息。其中状态STATUS有:

UNUSED - Online redo log has never been written to. This is the state of a redo log that was just added, or just after a RESETLOGS, when it is not the current redo log.(从未被联机重做日志写过的日志组,出现这种情况的要么是刚增加的,要么是该组不是当前在用重做日志组时RESETLOGS后的状态。)

CURRENT - Current redo log. This implies that the redo log is active. The redo log could be open or closed.(当前在用的重做日志组)

ACTIVE - Log is active but is not the current log. It is needed for crash recovery. It may be in use for block recovery. It may or may not be archived.(活跃的日志组,但不是当前在用的。崩溃恢复时需要该状态的日志组信息,它可能已归档也可能未归档。这就是为什么switch logfile后过一段时间状态才会是INACTIVE。)

CLEARING - Log is being re-created as an empty log after an ALTER DATABASE CLEAR LOGFILE statement. After the log is cleared, the status changes to UNUSED.(表明ALTER DATABASE CLEAR LOGFILE后,日志正在被重建为一个空日志,重建成功后状态为UNUESD.

CLEARING_CURRENT - Current log is being cleared of a closed thread. The log can stay in this status if there is some failure in the switch such as an I/O error writing the new log header.(表明正在清除当前日志文件中的已关闭线程,如果切换时发生某些故障,如写入新日志标题时的I/O错误,则该日志可以停留在该状态。)

INACTIVE - Log is no longer needed for instance recovery. It may be in use for media recovery. It might or might not be archived.(表明例程恢复不再需要该日志组。它可能已归档也可能未归档。)

来自 “ ITPUB博客 ” ,链接:http://blog.itpub.net/22466621/viewspace-1049216/,如需转载,请注明出处,否则将追究法律责任。

下一篇: 趣味SQL连载1
请登录后发表评论 登录
全部评论

注册时间:2011-03-10

  • 博文量
    13
  • 访问量
    26596