Query to check sync between Primary and Standby databases

For Single Instance: Primary: set lines 300 pages 3000 select max(sequence#) Primary from v$archived_log; You can check the sync status of standby database from Primary database also. set lines 300 pages 3000 select max(sequence#) Standby from v$archived_log where applied='YES'; where, you can check the destination for which standby database is configured. Standby: set lines 300 pages 3000 select max(sequence#) Standby from v$archived_log where applied='YES'; For RAC: Primary: set lines 300 pages 3000 select thread#, max(sequence#) from v$archived_log group by thread# order by 1; Standby: set lines 300 pages 3000 select thread#, max(sequence#) from v$archived_log where applied='YES' group by thread# order by 1;