apache pig - I would like to transform a map into a field in a Pig Latin script -

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the description of tuples of relation (a) follows: {a: int, b: int, c: map[]} map contains 1 chararray key not predictable. example, sample of tuples is:

(1, 100, [key.152#hello]) (8, 110, [key.3000#bonjour]) (5, 103, [key.1#hallo]) (5, 103, []) (8, 104, [key.11#buenosdias]) ...

i transform relation (a) b relation b description be: {a: int, b: int, c: chararray}

with sample, give:

(1, 100, hello) (8, 110, bonjour) (5, 103, hallo) (8, 104, buenosdias) ...

(i want filter empty maps too)

any ideas?

thank you.

though writing udf right solution, if want hack quick following solution using regex might help.

a = load 'sample.txt' (a:int, b:int, c:chararray); b = foreach generate a, b, flatten(strsplit(c, '#', 2)) (key:chararray, value:chararray); c = foreach b generate a, b, flatten(strsplit(value, ']', 2)) (value:chararray, ignore:chararray); d = filter c value not null;  e = foreach d generate a, b, value; store e 'output/e';

for sample input 

1       100     [key.152#hello] 8       110     [key.3000#bonjour] 5       103     [key.1#hallo] 5       103     [] 8       104     [key.11#buenosdias]

the above code produces following output:

1       100     hello 8       110     bonjour 5       103     hallo 8       104     buenosdias

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