Database level supplemental logging is an Oracle requirement that ensures that the Oracle redo log on the source database contains the information required to describe all data changes completely. Enabling supplemental logging is a requirement for all redo log mining replication solutions and not specific to Dbvisit Replicate.
Turning on supplemental logging ensures additional information is inserted into redo stream in order to facilitate replication. The extra level of overhead of adding this information into the redo log is generally less than 1%.
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