We recently started the process of continuous migration (initial load + CDC) from an Oracle database on RDS to S3 using AWS DMS. The DB is using LogMiner.
the problem that we have detected is that the CDC records of type Update only contain the data that was updated, leaving the rest of the fields empty, so the possibility of simply taking as valid the record with the maximum timestamp value is lost.
Does anyone know if this can be changed or in what part of the DMS or RDS configuration to touch so that the update contains the information of all the fields of the record?
Thanks in advance.
Supplemental Logging at table level may increase what is logged, but that will also increase total volume of log data written for a given workload.
Many Log Based Data Replication products from various vendors require additional supplemental logging at the table level to ensure the full row data for updates with before and after change data is written to the database logs.
re: https://docs.oracle.com/database/121/SUTIL/GUID-D857AF96-AC24-4CA1-B620-8EA3DF30D72E.htm#SUTIL1582
Pulling data through LogMiner may be possible, but you will need to evaluate if it will scale with the data volumes you need.