In Dataguard, we can protect the application data on physical databases by applying logs with delay option.
This can be configured both on primary and standby
on primary #
set delay parameter in log_archive_dest_2 parameter which ships logs to standby database. Here primary database will ship the archive logs with delay minuted to the standby database
*.log_archive_dest_2='SERVICE=TO_SDB12C delay=30 NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES, PRIMARY_ROLE) DB_UNIQUE_NAME=sdb12c'
On standby #
we can start applying archive logs with delay option
sql> alter database recover managed standby database using current logfile DELAY 30 disconnect;
we can cancel time delay option using following command# SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE NODELAY;when we are using nodelay option, MRP process will skip delay minutes
and applied archive logs to the standby database. we can avoid using delay option
by enabling flashback on both primary and standby databases :)
This can be configured both on primary and standby
on primary #
set delay parameter in log_archive_dest_2 parameter which ships logs to standby database. Here primary database will ship the archive logs with delay minuted to the standby database
*.log_archive_dest_2='SERVICE=TO_SDB12C delay=30 NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES, PRIMARY_ROLE) DB_UNIQUE_NAME=sdb12c'
On standby #
we can start applying archive logs with delay option
sql> alter database recover managed standby database using current logfile DELAY 30 disconnect;
we can cancel time delay option using following command# SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE NODELAY;when we are using nodelay option, MRP process will skip delay minutes
and applied archive logs to the standby database. we can avoid using delay option
by enabling flashback on both primary and standby databases :)
