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Re: Optimizing hive queries
Hello Owen,

Thanks for your reply.

I am seeing its providing the advantage which Avro provided , of adding and
removing fields.

Can you please write some sample code for hive table which is partitioned
and each partitioned has different schema.

I tried searching but could not find any example.

Thanks in advance for your help.

Regards,

Jagat Singh

On Fri, Mar 29, 2013 at 4:48 PM, Owen O'Malley <[EMAIL PROTECTED]> wrote:

> Actually, Hive already has the ability to have different schemas for
> different partitions. (Although of course it would be nice to have the
> alter table be more flexible!)
>
> The "versioned metadata" means that the ORC file's metadata is stored in
> ProtoBufs so that we can add (or remove) fields to the metadata. That means
> that for some changes to ORC file format we can provide both forward and
> backward compatibility.
>
> -- Owen
>
>
> On Thu, Mar 28, 2013 at 10:25 PM, Jagat Singh <[EMAIL PROTECTED]>wrote:
>
>> Hello Nitin,
>>
>> Thanks for sharing.
>>
>> Do we have more details on
>>
>> Versioned metadata feature of ORC ? , is it like handling varying schemas
>> in Hive?
>>
>> Regards,
>>
>> Jagat Singh
>>
>>
>>
>> On Fri, Mar 29, 2013 at 4:16 PM, Nitin Pawar <[EMAIL PROTECTED]>wrote:
>>
>>>
>>> Hi,
>>>
>>> Here is is a nice presentation from Owen from Hortonworks on "Optimizing
>>> hive queries"
>>>
>>> http://www.slideshare.net/oom65/optimize-hivequeriespptx
>>>
>>>
>>>
>>> Thanks,
>>> Nitin Pawar
>>>
>>
>>
>