REDO LOG MEMBER STATUS and REDO LOG GROUP STATUS

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程序员紫龙 2022-08-12 20:35:42 ©著作权

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V$log

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.

V$logfile
Status of the log member:

· INVALID - File is inaccessible

· STALE - File's contents are incomplete

· DELETED - File is no longer used

· null - File is in use