The system has 5 components to it: a normalized log of credit transactions, a denormalizer that takes log messages, combines them, and computes fields to be in the format you want for their SQL schema, a batcher that collects the completed rows and uploads them to s3 as files that can be imported into redshift, which once uploaded send commands to redshift to update the appropriate tables, and finally a cache that handles queries from the client and acts as a gateway to the redshift cluster.