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From Francis Christopher Liu <fc...@yahoo-inc.com>
Subject Re: Selective updates using HCatOutputFormat.setSchema()?
Date Fri, 04 Nov 2011 22:55:57 GMT
Hey Sushanth, 

Thanks for replying. Just for further clarification. In sql terms will it
look like this:

update foo set col2='new value' where ....

Or will it be

Update foo set col1=NULL, col2='new value', col3=NULL where....


I'm hoping it's the first since my intent is just to update col2.

-Francis

On 11/4/11 2:48 PM, "Sushanth Sowmyan" <khorgath@gmail.com> wrote:

>Yes, it is possible to do that, and it is intended :) - your table
>still has col1 and col3 as part of its schema, and when people read
>that table, they will get nulls for col1 and col3.
>
>-Sushanth
>
>On Thu, Nov 3, 2011 at 2:57 PM, Francis Christopher Liu
><fcliu@yahoo-inc.com> wrote:
>> Hi,
>> I'd like to clarify wether this selective column updates are supported
>>as
>> part of HCatOutputFormat.setSchema().
>> If I have an unpartitioned table:
>> foo(int col1, int col2, int col3)
>> Would it be possible for me to just pass column "col2" when calling
>> setSchema? For columnar stores (ie Hbase) it would be more efficient
>>just to
>> write out the values that we want updated instead of the entire row.
>> -Francis


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