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From Nate McCall <n...@riptano.com>
Subject Re: Newbie question - fetching multiple columns of differentdatatypes and conversion from byte[]
Date Sat, 25 Dec 2010 13:16:57 GMT
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
>

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