From the launch of oracle 12c, there is a new feature called transaction level failover! everyone recall that.
this means if there is an active transaction STILL running during the write node die, during the write master failover to another node and after the same transaction will KEEP running without any rerun of the transaction, which may cause duplicate of records as part of record already DMLed before it failover.
any information on this feature ? any URL can refer this feature of Oracle 12c really working ? or it means this: https://docs.oracle.com/database/121/JJDBC/ocitaf.htm#JJDBC28835?
I am not sure if Oracle 12c really can do it! MariaDB can do it with its proxy !