I am trying to get my hands around RMAN and issues the command
restore database preview summary and I see below.

Can somebody explain the following lines?

Media recovery start SCN is 614309
Recovery must be done beyond SCN 614318 to clear data files fuzziness.

a) where are these numbers comming from?
b) what recovery syntax would I use to recovery my DB up to the moment it
was shutdown, 614319, 614320, ......
c) If I chose to use a recovery until scn # syntax how would I correlate that
to a time my DB would be recovered


restore database preview summary
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List of Archived Logs in backup set 4544
Thrd Seq Low SCN Low Time Next SCN Next Time
---- ------- ---------- --------- ---------- ---------
1 349 614293 22-AUG-10 614323 22-AUG-10

List of Archived Log Copies
Key Thrd Seq S Low Time Name
------- ---- ------- - --------- ----
4694 1 350 A 22-AUG-10 /oracle/data/pri/arch/arch_350_1_727035906.arc
4695 1 351 A 22-AUG-10 /oracle/data/pri/arch/arch_351_1_727035906.arc
4696 1 352 A 22-AUG-10 /oracle/data/pri/arch/arch_352_1_727035906.arc
4697 1 353 A 22-AUG-10 /oracle/data/pri/arch/arch_353_1_727035906.arc
4698 1 354 A 23-AUG-10 /oracle/data/pri/arch/arch_354_1_727035906.arc
4699 1 355 A 23-AUG-10 /oracle/data/pri/arch/arch_355_1_727035906.arc
4700 1 356 A 23-AUG-10 /oracle/data/pri/arch/arch_356_1_727035906.arc
Media recovery start SCN is 614309
Recovery must be done beyond SCN 614318 to clear data files fuzziness
Finished restore at 23-AUG-10