24.12.2015 05:31, 'Leyne, Sean' wrote: > > With today's unlimited availability of disk space and silly-low cost per GB > for storage, would an argument to dispense with the delta and simply store a > full copy of the record (not including BLOB) be worthy of discussion?
It's not about storage cost, but about IOPS. Bigger record = more I/O for the same data = slower performance. Situation is better for SSDs, but "silly-low cost" does not really apply there. > I know that Jim has mentioned that in his later db engine he has adopted a > reverse approach which has the latest version stored in full and for > transactions required back versions responsible processing the deltas. In > this way, the latest version of the row are always complete so that the back > versions can be dropped very efficiently. Isn't it exactly how Firebird works? Dmitry
