Handling Oracle Sequences

Although GoldenGate supports the replication of Oracle Sequence values, there are a number of issues we need to be aware of. For example, GoldenGate will support Oracle Sequence replication for CDC if checkpoints are not maintained. This is dependent on the SPECIALRUN parameter that exists in the Replicat parameter file. However, they are not supported for initial loads in which the source data is derived from the source tables and not the redo logs. So, the sequence values are not extracted.

For bidirectional (active-active) environments, the database sequences must generate values on the target database independent to the source. Note that in a cascade environment, GETAPPLOPS must be enabled on the Extract to capture sequence values replicated by the Replicat process.

Sequence gaps often occur in an Oracle database, depending on the associated sequence, cache size, and number of instances in the RAC environment. However, unless the NOCHECKSEQUENCEVALUE parameter...