5.163 DBA_LOGSTDBY_HISTORY
DBA_LOGSTDBY_HISTORY
displays the history of switchovers and failovers in a Data Guard configuration.
It does this by showing the complete sequence of redo log streams processed or created on the local system, across all role transitions. (After a role transition, a new log stream is started and the log stream sequence number is incremented by the new primary database.). This view is for logical standby databases only.
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Lists the sequence numbers for all log streams created or applied on the local system. Note: A value of 0 indicates an unknown sequence order; this is reserved for future log streams. |
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Description of the log stream processing:
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Describes how the log stream was started:
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Database identifier of the primary database that created the log stream |
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Lowest system change number (SCN) in the current log file |
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Highest system change number (SCN) in the current log file |
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Time of the first SCN entry ( |
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Time of the last SCN entry ( |
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Unique database name ( |
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SCN that should be used to flashback a failed primary (that created the log stream) or to flashback a bystander logical standby database following a failover, in the context of the associated redo log stream. It is the SCN up to which redo for the associated log stream can be merged safely in all databases using local copies of archived logs received from the primary database. In order to apply changes beyond this following a failover, you will need to fetch and mine the redo logs from the failover target. |
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Strict upper bound on the SCN up to which SQL Apply has applied redo records before it switched to a new log stream (either because it was activated and became the primary database, or in the case of a bystander logical standby database where it switched to a new log stream to accommodate a new primary database). |
Note:
In a CDB, this view shows data only when queried in the root.