As far as I remember, a restore validate only validates the level 0 incremental
backup that RMAN would restore first, before restoring the level 1 incremental
and whatever archived logs etc to bring the restore up to date.
I've never run a validate on a non-incremental backup, but I would imagine that
doing so would validate all required backup pieces. For incremental, you only
validate the level 0, at least, in all the tests I've done with:
Set until sequence n;
Restore validate dstabase;
The reason being that you cannot run a 'recover validate database' command, so
you don't get the level 1 and archived logs being validated.
Sent from my Android device with K-9 Mail. Please excuse my brevity.