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From Roshan Dawrani <roshandawr...@gmail.com>
Subject Re: Newbie question - fetching multiple columns of differentdatatypes and conversion from byte[]
Date Sat, 25 Dec 2010 13:28:50 GMT
Thanks a lot for the references. Will check them out first before asking the
next question.

On Sat, Dec 25, 2010 at 6:46 PM, Nate McCall <nate@riptano.com> wrote:

> See the following PDF for some additional detail on hector:
> http://www.riptano.com/sites/default/files/hector-v2-client-doc.pdf
>
> There is a also a project with some basic stand-alone examples that
> may be helpful:
> https://github.com/zznate/hector-examples
>
> And Riptano maintains a Java port of a Twitter example using Hector:
> https://github.com/riptano/twissjava
>
> On Sat, Dec 25, 2010 at 12:22 AM,  <roshandawrani@gmail.com> wrote:
> > Can you please point me an example of that or some Hector API
> documentation?
> >
> > I am currently using IndexedSliceRangeQuery to filter on a 2ndary index
> and fetching all columns of the matching rows - using range start/end =
> null. Can the option you suggest be used with the 2ndry index filtering? I
> would appreciate very much seeing an example.
> >
> > Does it make any performance difference whether that conversion is done
> by Hector/Cass or by the app?
> >
> > Thanks.
> > Roshan
> > ---------------------------------------------------
> > Sent from BlackBerry
> >
> > -----Original Message-----
> > From: Jonathan Ellis <jbellis@gmail.com>
> > Date: Sat, 25 Dec 2010 00:05:44
> > To: user<user@cassandra.apache.org>
> > Reply-To: user@cassandra.apache.org
> > Subject: Re: Newbie question - fetching multiple columns of different
> >  datatypes and conversion from byte[]
> >
> > Or you can specify the types with the column name instead of doing a
> slice.
> >
> > On Fri, Dec 24, 2010 at 11:23 PM, Nate McCall <nate@riptano.com> wrote:
> >> In the case where you have different value types within the same
> >> slice, yes, you must handle the conversion yourself and
> >> ByteBufferSerializer is the easiest way to do that.
> >>
> >> On Fri, Dec 24, 2010 at 10:44 PM, Roshan Dawrani
> >> <roshandawrani@gmail.com> wrote:
> >>> Hi,
> >>>
> >>> I am new to Cassandra and Hector and have a basic question on fetching
> >>> multiple columns of a row that have mixed data types.
> >>>
> >>> So, I am basically doing equivalent of "Select dateCol1, dateCol2,
> >>> stringCol1, intCol1 from a_table where key in (?, ?, ?...)"
> >>>
> >>> My question is do I need to do the conversion of columns from byte[] to
> >>> Date/String/Int myself after taking out data from the ColumnSlice?
> >>>
> >>> For saving the same data, while adding the columns, I was able to tell
> which
> >>> serializer to use, but slice queries seem to take only one
> ValueSerializer
> >>> for all columns being retrieved. So, if I have got it correctly, I can
> only
> >>> use ByteBufferSerializer in the Hector API slice query call and then do
> >>> further data-type specific conversion myself at the app level?
> >>>
> >>> --
> >>> Roshan
> >>> Blog: http://roshandawrani.wordpress.com/
> >>> Twitter: @roshandawrani
> >>> Skype: roshandawrani
> >>>
> >>
> >
> >
> >
> > --
> > Jonathan Ellis
> > Project Chair, Apache Cassandra
> > co-founder of Riptano, the source for professional Cassandra support
> > http://riptano.com
> >
>



-- 
Roshan
Blog: http://roshandawrani.wordpress.com/
Twitter: @roshandawrani <http://twitter.com/roshandawrani>
Skype: roshandawrani

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