AWS’s Database Migration Service (DMS) is often misunderstood as a service that can only migrate your data to the cloud. But the service could be very useful for replicating data between the two datastores within the cloud as well. In our case, both of our datastores – RDS (MySQL) and Redshift were already in the cloud. The MySQL database is our primary OLTP database and many of our employees login to an internal application to modify data within this database. This database contains all of our dimension tables. Our reporting dashboard connects with our data warehouse built on Redshift. This database contains all of our fact tables. In order to run the reports accurately it’s important that all the modifications done to the dimension tables in MySQL are transferred to Redshift in timely manner.