V$ARCHIVED_LOG 【控制文件记录的关于已经归档的日志信息,当redo被归档后会立即记录该记录】
V$ARCHIVED_LOG displays archived log information from the control file, including archive log names. An archive log record is inserted after the online redo log is successfully archived or cleared (name column is NULL if the log was cleared). If the log is archived twice, there will be two archived log records with the same THREAD#, SEQUENCE#, and FIRST_CHANGE#, but with a different name. An archive log record is also inserted when an archive log is restored from a backup set or a copy and whenever a copy of a log is made with the RMAN COPY command.

column NAME format a40

  Indicates the number of times this file has been backed up. Values range from 0-15. If the file has been backed up more than 15 times, the value remains 15.
  Time when the archiving completed
   Status of the archived log:
   A - Available
   D - Deleted
   U - Unavailable
   X - Expired  
   Creator of the archivelog:
   ■ ARCH - ARCH process
   ■ FGRD - Foreground process
   ■ RMAN
   ■ SRMN - RMAN at standby
   ■ LGWR - LGWR process
   Registrar of the entry:
   ■ RFS
   ■ ARCH - ARCH process
   ■ FGRD - Foreground process
   ■ RMAN
   ■ SRMN - RMAN at standby
   ■ LGWR - LGWR process     
  Size of the archived log (in blocks)   

Contains log history information such as which logs have been archived and the SCN range for each archived log.

This view contains information about redo log files.

column MEMBER format a60
select *from v$logfile;

displays log file information from the control file.

   Archive status (YES or NO)
   Log status:
   ■ 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.
   ■ CURRENT - Current redo log. This implies that the redo log is active. The redo log could be open or closed.
   ■ 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.
   ■ 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.
   ■ 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.
   ■ INACTIVE - Log is no longer needed for instance recovery. It may be in use for media recovery. It might or might not be archived.
   ■ INVALIDATED - Archived the current redo log without a log switch.