In one of my previous posts I have described the rationale for using a checkpoint table in the Replicat process. This is a summary of all possible combinations of Replicat process and which of them are able of (not) using checkpoint table.
One of the key aspects for replication is checkpointing. A target database checkpoint tells which transactions are actually committed and which not yet. This is a key aspect of transactional replication. Let’s look how that works for the Oracle GoldenGate Classic Replicat.
According to the Oracle database documentation there are two types of constraints: DEFERRED and NOT DEFERRED. The first one can be evaluated at the and of the transaction, and the second one if validated immediately. On the other hand Oracle GoldenGate can handle the replication when the target uses both of them. Let’s find out …