Oracle is marketing Exadata to our company, and they're focusing on Smartscan, which is, advertised 10x more effective than traditional solution. I don't really understand (and somewhat don't really believe) this solution, because they assume that data is put on separated storage, and no indexes are used, so "1TB data was scanned and only 2MB is returned".
So, I want to ask you: is Smartscan really effective. Is it true solution that greatly improves performance or just a buzzword?
It's definitely more than a buzzword. Whether it's effective will depend on your database. It offloads part of the work to the storage server which reduces data volume over the storage server network and the CPU on database host to process it. If your database doesn't max out these resources then you won't see a benefit. It seems to be me only large data warehouses would really get much from it.