Yesterday, I was working on a simple Golden Gate replication between two Oracle databases. Everything worked as expected, the source and target schemas were synchronized and the replication lag was about 0 seconds.
Unfortunately; after a couple of hours, I notice a 2 hours lag on the replicat…
After some research on GoldenGate and with some queries on v$session and v$sql, I realize that the lag is due to a 100 million rows table on which there is no primary key or unique key defined.
Important point: I was not allowed to add constraints on the source database!