On Sep 5, 2012, at 6:30 PM, Prasanth J wrote:
> 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?
Yes.
Alan.
> 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
>>>
>>
>
