count_bool受到单个元组的影响,当我转储它时,它具有以下输出:
(0)
...
(1)
(0)
...
(0)
所以如果有100 - (0)和20 - (1)我希望输出为:
(1, 20)
(0, 100)
这是我试图压扁和计算
count_by_xy = foreach count_by_subject generate flatten($0), COUNT($0);
2013-07-09 00:05:43,590 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1045:
Could not infer the matching function for org.apache.pig.builtin.COUNT as multiple or none of them fit. Please use an explicit cast.
我的问题是什么?
答案 0 :(得分:0)
'colName'是分配给1-tuple列的名称:
count_group = group count_bool by colName;
'结果'有我要找的东西:
result = foreach count_group generate $0, COUNT(count_bool);
$0
引用第一列的值。
flatten
用于取消嵌套元组,这里不需要。