这些步骤应该很简单：
按原样加载数据
使用substring函数生成四个新列
例如，您应该能够将c2提取为：

SUBSTRING(inputstring, 5, 8)

延伸丹尼斯的答案。假设字段存储为chararray

A = LOAD 'data.txt' as (f1:chararray);
B = FOREACH A GENERATE 
         SUBSTRING(f1,0,2) as A1,
         SUBSTRING(f1,2,4) as A2,
         SUBSTRING(f1,4,6) as A3,
         SUBSTRING(f1,6,8) as A4;
DUMP B;