Earlier quoted context omitted.
It's highly unlikely you could ever use generic enough SQL to go from open source DB or Oracle. Best case you wouldn't be getting the best performance out of your open source database and then you wouldn't be getting the best performance out of Oracle. It's better to build for the platform you have than build for a mythical common platform that contains the minimum features of syntax of all of other DBMS (which proba…
OK, your point is not that DB changes won't happen -- but that there is no use to prepare and think about it beforehand. Sounds reasonable to me.
Kind of like premature optimization, "premature compatibility" can be a performance/labour-hours killer.