Re: How to run a UDF on the result of GROUP BY

[Rekha Joshi]

Depends on how you have coded your UDF.For some examples on how to work with 
UDF refer http://hadoop.apache.org/pig/docs/r0.5.0/udf.html

Cheers,
/R


On 1/18/10 1:23 PM, "Anthony Urso" <antho...@cs.ucla.edu> wrote:

I can't figure out how to run a UDF on the result of "GROUP BY" from
the current documentation.

I'd like to do something along these lines:

A = LOAD 'A';
B = LOAD 'B';
C = JOIN A BY $0, B by $0;
D = GROUP C BY A::$0;
E = FOREACH D GENERATE FLATTEN(my.UDF(??????));
STORE E IN 'E';

Specifically, what goes in the UDF call?  I've tried to use "D" there,
but it errors out claiming a bad alias.  Using "C" compiles, but does
not seem right to me.

Also, what is actually passed to the UDF.exec method in this case?

Thanks,
Anthony