As per Alan F Gates in "Programming Pig" :
*Pig does not know whether integer values in baseball are stored as ASCII
strings, Java serialized values, binary coded decimal, or some other
format. So it asks the load function. It is the responsibility of the load
function to cast bytearrays to other types. In general this works nicely,
but it does lead to a few corner cases where Pig does not know how to cast
a bytearray. In particular, if a UDF returns a bytearray Pig will not know
how to perform casts on it, because that bytearray is not generated by a
load function.*
I have a UDF that does exactly this, return a Tuple of bytearrays and I am
unable to cast them to other types. *How can I get around this?
*
For eg, UDF(A..Z) returns a tuple (bytearray, bytearray...bytearray).
A = load 'input' using PigStorage();
B = FOREACH A GENERATE FLATTEN(UDF('arg1', 'arg2', 'arg3')) as (p,q,r);
But if I try
C = FOREACH B GENERATE (chararray)p as p; //FAILS OUT WITH CAST EXCEPTION -
bytearray cannot be cast to chararray
OR IF I TRY
C = FILTER B BY p matches "pig"; //FAILS OUT WITH CAST EXCEPTION-
bytearray cannot be cast to chararray
Thanks,
Prashant
