Ahh.. Now it makes more sense.
I think I got the solution. I was adding to List<Tuple> and then finally
creating a DataBag with that list.. Instead I should create a bag and keep
adding to it..!! Is that correct?
Thanks Alan.
Thanks
-- Prasanth
On Sep 5, 2012, at 9:24 PM, Alan Gates <ga...@hortonworks.com> wrote:
> You cannot modify a bag once it is written. The implementation is written
> around the assumption that bags are immutable after they are written.
>
> Creating a new bag should not create an OOM exception, as bags are built to
> spill when they grow too large. In fact it's this spilling feature that
> makes in place modification impossible.
>
> Alan.
>
> On Sep 5, 2012, at 6:08 PM, Prasanth J wrote:
>
>> Hello devs
>>
>> I have specific case where I need to modify the contents (remove a field
>> from each tuples) of Databag but I want to do it in-place and do not want to
>> create another databag with new set of tuples.
>> The situation is, say I have the following input tuple for an UDF
>>
>> {(111,222,3,121), (112,223,2,131), (113,224,4,141)}
>>
>> I want to iterate through this bag and generate an output bag removing the
>> 3rd the of each tuples in the bag to get the following output
>> {(111,222,121), (112,223,131), (113,224,141)}
>>
>> Since the number of tuples in this bag are expected to be large I cannot
>> create new set of tuples and create a bag, as this will cause OOM exception.
>>
>> Also I do not want to flatten this bag as this bag will be passed to
>> DISTINCT operator for computing distinct elements in the bag.
>> As seen from the javadocs for DataBag, there is no way to convert a bag on
>> the fly. I wonder if there is any other way to solve this?
>>
>> Thanks
>> -- Prasanth
>>
>
