Oracle Data Guard Apply and Transport Lag

Shows transport and apply lag on the standby. Used to monitor DR readiness and potential data loss window.

#data-guard#standby#lag

oracle · sql

-- Standby üzerinde
SELECT name, value, unit, time_computed
FROM   v$dataguard_stats
WHERE  name IN ('transport lag','apply lag','apply finish time');

SELECT process, status, thread#, sequence#, block#
FROM   v$managed_standby
WHERE  process IN ('MRP0','RFS');

Operational Notes & Remediation Guidance

Verify in a staging environment prior to running in production. This is a read-only diagnostic query; it does not acquire exclusive locks.

Production Safety & Execution Standards

This script is designed for read-only diagnostics; it does not alter schema or modify data directly.
Prior to executing on production systems under high load, verify the target database version (Min. Version: 11g).
Exercise caution with mutating actions (e.g., terminating sessions or dropping indexes) referenced in the notes section.

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