Transaction Guard and Application Continuity

Transaction Guard:  A new feauture in version 12c.  Transaction guard provides a way to keep track of transaction state by using a logical transaction identifier which maps to a dataabase transactio_id.  If there is a failure, the applciation connection can query the transaction status using logical transaction_id to determine if a transaction is commited or not.  There are two parameters when creating a service as transaciton guard.  commit_outcome:  to determine if a logical transaction is tracked or not.  retention how long to retend in the database (default 86400 seconds = 1 day).

srvctl add service -d dba12c -service TGDBA12C -preferred DBA12C1 -available DBA12C2 -commit_outcome TRUE -retention 86400

Application Continuity:  

Application Continuity is a new feature in 12c using the transaction guard.  It attempts to mask the outage by rebuilding the database session and resubmitting the pending work.  It used client-side JDBC driver 12c, Universal connection Pool 12c, and Oracle WeblOGIC sERVER 12.1.2 class.

-failovertype TRANSACTION

-commit_outcome  TRUE

srvctl add service -d dba12c -service ACDBA12C -preferred DBA12C1 -available DBA12C2 -commit_outcome TRUE -retention 86400 -failovertype TRANSACTION -failoverretry 10 -failoverdelay 5 -replay_int_time 1200