read repair and column range queries

[Thorsten von Eicken <tv...@rightscale.com>]

Looking at the docs, I can't conclusively answer this question:

Suppose I make this CQL query with consistency factor 1 and read-repair
100%:
select 'a'..'z' from cf where key = 'xyz' limit 5;
Suppose the node I connect to has the key and responds with (improvised
syntax):
['a'->0, 'c'->2, 'e'->4, 'g'->6, 'i'->8]
Suppose another node has a column 'b'->1, would this be caught by the
read repair?

The question really boils down to whether the digest query being sent is
the same as the one above, or whether it's more of the form "select a,
c, e, g, i from cf where key = xyz" and thus only checks whether the
column values are in agreement.

Thanks!
Thorsten

Re: read repair and column range queries

[Nate McCall <na...@datastax.com>]

The digest is based on the results of the same query as applied on
different replicas. See the following for more details:
http://wiki.apache.org/cassandra/ReadRepair
http://www.datastax.com/docs/1.0/dml/data_consistency

On Wed, Nov 30, 2011 at 11:38 PM, Thorsten von Eicken
<tv...@rightscale.com> wrote:
> Looking at the docs, I can't conclusively answer this question:
>
> Suppose I make this CQL query with consistency factor 1 and read-repair
> 100%:
> select 'a'..'z' from cf where key = 'xyz' limit 5;
> Suppose the node I connect to has the key and responds with (improvised
> syntax):
> ['a'->0, 'c'->2, 'e'->4, 'g'->6, 'i'->8]
> Suppose another node has a column 'b'->1, would this be caught by the
> read repair?
>
> The question really boils down to whether the digest query being sent is
> the same as the one above, or whether it's more of the form "select a,
> c, e, g, i from cf where key = xyz" and thus only checks whether the
> column values are in agreement.
>
> Thanks!
> Thorsten