DW migration

Our sales people have asked us to look at migrating a small (less than 3TB) DW system from another vendor’s database to Oracle. The DW database migration is conceptually not too difficult – we keep the user layer logically the same as now so they do not have to make major changes to their reporting tools and replace all of the current data load scripts with whizzy OWB maps to move the source data into the DW.

The big issue with the migration is the choice of platform. The current DW is on dedicated MPP hardware; we have no option to reuse it. Storage is relatively simple; it will be SAN. The customer already uses SAN and NAS extensively in their business, so putting the DW on to a SAN is a no-brainer for them. The hard choice is for processing. At present we have three choices: the customer re-uses one of their “mothballed” large UNIX boxes; we kit them out with some nice new low-cost Linux blade servers, or we put in a similar cluster running Windows. The rational for considering two of these is politically motivated. I know which I prefer technically, but my preferences are not that important at the end of the day.