I was initially thinking to create a Transactional Replication copy of a couple databases to use to populate a staging database which ultimately will populate a data mart for DW.
Would this be the preferred way or would an ODS be better? So populate the ODS from the PROD OLTP which will then populate the staging db and then the DW. If so, what are the performance issues that may arise when hitting the PROD server to populate the ODS?