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From Sameer Farooqui <cassandral...@gmail.com>
Subject Re: Is there a way to read a Double value from the CLI?
Date Tue, 19 Jul 2011 19:54:49 GMT
k, thanks for the clarification Nate.


On Tue, Jul 19, 2011 at 10:14 AM, Nate McCall <nate@datastax.com> wrote:

> The DoubleSerializer in Hector predates Cassandra's DoubleType and was
> thus designed to stick values in a LongType or BytesType comparator.
> Because of this, we are calling Double.doubleToRawLongBits and
> Double.longBitsToDouble underneath, so this may not be what you
> expect.
>
> I'll add another serializer(s) for the new set of types.
>
> Now if only we had a client mailing list to which client-impacting
> changes could be sent ...  :-)
>
> On Mon, Jul 18, 2011 at 4:50 PM, Jonathan Ellis <jbellis@gmail.com> wrote:
> > org.apache.cassandra.db.marshal.DoubleType should work, then.  the
> > cast shouldn't be necessary if the doubletype is actually in the
> > schema either.
> >
> > On Mon, Jul 18, 2011 at 4:34 PM, Sameer Farooqui
> > <cassandralabs@gmail.com> wrote:
> >> Yup, Jonathan, I was just temporarily returning the value as LongType
> b/c I
> >> couldn't find a DoubleType. Since LongType returned something, I know
> that
> >> the data is there.
> >>
> >> Thanks for that link, Jeremy. I'm guessing DoubleType hasn't found its
> way
> >> into the CLI yet, b/c I tried this and got an error:
> >>
> >> [default@DemoKS] get
> DemoCF[ascii('ABC_100000000020')][long(20090101000000)]
> >> as DoubleType;
> >> Unknown comparator 'DoubleType'. Available functions: bytes, integer,
> long,
> >> lexicaluuid, timeuuid, utf8, ascii, countercolumn.
> >>
> >>
> >>
> >>
> >> On Mon, Jul 18, 2011 at 2:28 PM, Jonathan Ellis <jbellis@gmail.com>
> wrote:
> >>>
> >>> "get X as LongType" will give you the bytes in that column value
> >>> interpreted as a long.
> >>>
> >>> So it did exactly what you asked it to do :)
> >>>
> >>> On Mon, Jul 18, 2011 at 4:16 PM, Sameer Farooqui
> >>> <cassandralabs@gmail.com> wrote:
> >>> > I wrote some data to a standard column family (using Hector) with
> ASCII
> >>> > row-key, Long column name and Double column value.
> >>> >
> >>> > The CLI doesn't seem to have a double data type to interpret the
> column
> >>> > value for display.
> >>> >
> >>> > [default@DemoKS] get
> >>> > DemoCF[ascii('ABC_100000000020')][long(20090101000000)]
> >>> > as LongType;
> >>> > => (column=0000124597556740, value=4629084924887308954,
> >>> > timestamp=1310144024947000)
> >>> >
> >>> > But that value is not exactly correct. It should be:
> 29.813332976331914
> >>> >
> >>> >
> >>> > This is how I do the read in Hector:
> >>> >
> >>> >         ColumnQuery<String, Long, Double> columnQuery =
> >>> > HFactory.createColumnQuery(keyspace, ss, ls, ds);
> >>> >
> >>> >
> >>> >
> >>> >
> columnQuery.setColumnFamily("DemoCF").setKey("ABC_100000000020").setName(20090101000000L);
> >>> >
> >>> >         QueryResult<HColumn<Long, Double>> result =
> >>> > columnQuery.execute();
> >>> >
> >>> >         System.out.println("Query result: " + result.get());
> >>> >
> >>> >
> >>> > Is there a equivalent for that in Cassandra CLI?
> >>> >
> >>> > - Sameer
> >>> >
> >>> >
> >>>
> >>>
> >>>
> >>> --
> >>> Jonathan Ellis
> >>> Project Chair, Apache Cassandra
> >>> co-founder of DataStax, the source for professional Cassandra support
> >>> http://www.datastax.com
> >>
> >>
> >
> >
> >
> > --
> > Jonathan Ellis
> > Project Chair, Apache Cassandra
> > co-founder of DataStax, the source for professional Cassandra support
> > http://www.datastax.com
> >
>

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