V$LOG

V$LOG displays log file information from the control file.

Column Datatype Description
GROUP# NUMBER Log group number
THREAD# NUMBER Log thread number
SEQUENCE# NUMBER Log sequence number
BYTES NUMBER Size of the log (in bytes)
MEMBERS NUMBER Number of members in the log group
ARCHIVED VARCHAR2(3) Archive status (YES) or (NO)
STATUS VARCHAR2(16) 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 may or may not be archived.

FIRST_CHANGE# NUMBER Lowest system change number (SCN) in the log
FIRST_TIME DATE Time of the first SCN in the log