Please explain the difference between Crash recovery and Instance recovery.

When asked to compare two similar but different items, the easiest way to do this is to first define each item. You can then discuss their differences or similarities. As with most questions, keep your answers brief and to the point, and anticipate a follow-up question from the interviewer.

"While both of these terms are related to recovering data after a crash, they differ. A crash recovery occurs when an instance crashes in a single node database on startup. If this occurs In a RAC environment, the surviving nodes perform the same recovery for an instance. In this case, the recovery is called an instance recovery. The difference between these is that the startup process continues without the affected node."