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Hive >> mail # user >> hadoop.io.DoubleWritable v/s hive.serde2.io.DoubleWritable


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Re: hadoop.io.DoubleWritable v/s hive.serde2.io.DoubleWritable
Hive likely wishes to format the data differently then Hadoop does.
Hive re-uses what it can. I would diff the two .java files and find
out for yourself :)
On Tue, Jun 12, 2012 at 5:20 PM,  <[EMAIL PROTECTED]> wrote:
> Hi Edward,
>
> Sorry, If I was not clear. My question is around difference between DoubleWritable in hadoop and hive, other writables from hadoop works fine in hive.
> Hive.serde types are limited to Double, Byte, Short and Timestamp.
>
> I am using hive 0.8
>
> Richin
>
> -----Original Message-----
> From: ext Edward Capriolo [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, June 12, 2012 5:12 PM
> To: [EMAIL PROTECTED]
> Subject: Re: hadoop.io.DoubleWritable v/s hive.serde2.io.DoubleWritable
>
> If you use Double or double hive will automatically convert. I would always recommend the hive.serde types.
>
> Edward
>
> On Tue, Jun 12, 2012 at 4:56 PM,  <[EMAIL PROTECTED]> wrote:
>> Hi Guys,
>>
>>
>>
>> I am writing a UDF in hive to convert a double value to string, so the
>> evaluate method of my UDF class looks like
>>
>>
>>
>> import org.apache.hadoop.hive.ql.exec.UDF;
>>
>> import org.apache.hadoop.io.Text;
>>
>> //import org.apache.hadoop.io.DoubleWritable; - does not work
>>
>> import org.apache.hadoop.hive.serde2.io.DoubleWritable;
>>
>>
>>
>> public Text evaluate(DoubleWritable d){
>>
>>
>>
>> }
>>
>>
>>
>> When I looked at different UDF examples the Hadoop Writables seem to
>> work fine in case of Text and IntWritable but for DoubleWritable I was
>> getting an error. I figured out looking at couple of examples online
>> that I should use the DoubleWritable from hive.serde2 package instead of hadoop.io package.
>>
>>
>>
>> Can someone please explain why this special case for DoubleWritable?
>>
>>
>>
>> Thanks,
>>
>> Richin