If you delete the commit logs you are rolling back to exactly what was in the snapshot. When you take a snapshot it flushes the memtables first, so there is nothing in the commit log that is not in the snapshot. Rolling back to a snapshot is rollback to that point in time.
If you want to restore to any point in time you need snapshots + incremental snapshot + commit log (for things that have not made it to sstables). Otherwise there is a potential loss of data that has not been flushed to disk. This is different to what the DS docs are talking about. I'm not sure why they are saying delete the commit log, try asking on their forum http://www.datastax.com/support-forums/
On 2/05/2012, at 12:02 PM, Roshan wrote: