Writes under the same row key are atomic (even across column families) in theOn Thu, Dec 8, 2011 at 12:57 AM, Christof Bornhoevd
> Hi All,
> I'm using Cassandra 1.0.3 (with Hector 0.7). What is the granularity of
> atomic read and write operations with Cassandra. I.e. is the insert or
> update of an individual column an atomic operation (in the sense that it
> either fails or persists completely), or is the insert or update of an
> entire row in a ColumnFamily atomic?
> Similarly, if I read multiple columns of the same row, could the read
> operation interfere with a concurrent write operation on these same columns
> in a way that I might see some old and some new column values?
sense that they are either all persisted or none are. Note however that it is
possible for a insertion to fail for the client (say you get a
for the insertion to still be persisted.
There is however no isolation currently. It is possible for a read to
see a state
where only part of an insertion (even within the same row key) has been applied.
(CASSANDRA-2893 is open to try to add isolation).
> Cheers and thanks a lot for any kind help on this!