Quote from: PremiumCodeX on November 26, 2016, 09:34:53 PM

Quote from: CIYAM on November 21, 2016, 07:53:12 PM

Quote from: PremiumCodeX on November 21, 2016, 07:02:05 PM

How should a rollback happen in your view?

A real "rollback" would require that the transaction log would have kept the full details of any deleted record (no major DB in the world does that AFAIA).

So if you want to "reverse history" it would be easy enough to recover "deleted records" using the transaction log.

Hope that makes sense.

Correct me if I misunderstood something, but would not that require a MUCH bigger size of HDD? In addition, the log writing and reading speed would significantly increase that would result in slower DBs, would not it? At large DBs, speed is essential because some queries could take up to 20 or more minutes even without the mentioned idea.

Yes, I used MS SQL for a project www.blockchainsql.io. 450GB database. If you optimise right, queries can be lightning fast.