hadoop - タプルのHadoop PIG Max

Question

MAXPig でタプルのを見つけるにはどうすればよいですか?

私のコードは次のようになります。

A,20
B,10
C,40
D,5

data = LOAD 'myData.txt' USING PigStorage(',') AS key, value;
all = GROUP data ALL;
maxKey = FOREACH all GENERATE MAX(data.value);
DUMP maxKey;

これは 40 を返しますが、完全なキーと値のペアが必要です: C,40. 何か案は？

Answer 1

これは Pig 0.10.0 で動作します:

data = LOAD 'myData.txt' USING PigStorage(',') AS (key, value: long);
A = GROUP data ALL;
B = FOREACH A GENERATE MAX(data.value) AS val;
C = FILTER data BY value == (long)C.val;
DUMP C;

Answer 2

これを試して：

data = LOAD 'myData.txt' USING PigStorage(',') AS (key: chararray, value: int);

sorted = ORDER data BY value DESC;

limited = LIMIT sorted 1;

projected = FOREACH limited GENERATE key;

DUMP projected;