setReversed(true) sorts timeUUID in descending order.  thanks, -aj

On Sun, May 9, 2010 at 6:44 AM, Lee Parker <lee@socialagency.com> wrote:
You need to set the Reversed attribute on the sliceRange.  I don't know which library you are using, but it may be something like sliceRange.setReversed(true).

Lee Parker

On Sat, May 8, 2010 at 7:36 PM, AJ Chen <ajchen@web2express.org> wrote:
I have a column family for sorting time-uuid and expect to retrieve columns in descending order (i.e. latest on the top). but the following get_slice call returns column in ascending order.  Does cassandra sort time-uuid column in descending order by default? Should get_slice call return the most recent time-uuid?

    <ColumnFamily CompareWith="TimeUUIDType" Name="Index"/>

    ColumnParent columnParent = new ColumnParent(cf);
    SlicePredicate predicate = new SlicePredicate();
    SliceRange sliceRange = new SliceRange();
    sliceRange.setStart(new byte[] {});
    sliceRange.setFinish(new byte[] {});
    sliceRange.setCount(max);
    predicate.setSlice_range(sliceRange);
    return client.get_slice(keyspace, key, columnParent, predicate, ConsistencyLevel.ONE);

thanks,
-aj--





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AJ Chen, PhD
Chair, Semantic Web SIG, sdforum.org
http://web2express.org
twitter @web2express
Palo Alto, CA, USA