cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jonathan Ellis <jbel...@gmail.com>
Subject Re: Cassandra guarantees reads and writes to be atomic within a single ColumnFamily.
Date Wed, 13 Jan 2010 22:40:13 GMT
It's correct, if understood correctly.  We should probably just remove
it since it's confusing as written.

What it means is, if a write for a given row is acked, eventually,
_all_ the data updated _in that row_ will be available for reads.  So
no, it's not atomic at the batch_mutate level but at the
list<ColumnOrSuperColumn> level.

-Jonathan

On Mon, Jan 11, 2010 at 3:01 PM, Ran Tavory <rantav@gmail.com> wrote:
> The front page http://incubator.apache.org/cassandra/ states that "Cassandra
> guarantees reads and writes to be atomic within a single ColumnFamily."
> What exactly does that mean, and where can I learn more about this?
> It sounds like it means that batch_insert() and batch_mutate() for two
> different rows but in the same CF is atomic. Is this correct?
>
>

Mime
View raw message