Question

我想用猪计算2个和的除法

A = LOAD 's3://input' AS (filed1:chararray, filed2:int, field3:float, field4:float);
filtered_1 = FILTER A BY field3 >= 10;
filtered_2 = FILTER filtered_1  BY field4 >= 50;
grouped = GROUP filtered_2 BY field1;
B = FOREACH grouped GENERATE group as field1, SUM(A.field3)/SUM(A.field4) AS A_avg;

除了运行上一个命令时出现此错误：

ERROR grunt.Grunt: ERROR 1045: <line 5, column 55> Could not infer the matching function for org.apache.pig.builtin.SUM as multiple or none of them fit. Please use an explicit cast.

我找不到为什么因为我在执行总和之前使用GROUP，而且我已经通过了SUM文档而且我不知道与我写的内容有什么不同

Answer 1

grouped = GROUP filtered_2 BY field1;

grouped has no ACCESS to alias A . 

B = FOREACH grouped GENERATE group as field1, SUM(A.field3)/SUM(A.field4) AS A_avg;

"FOREACH grouped " has no access to alias A but directly to fields (field3, field4)






filtered_1 = FILTER A BY field3 >= 10;
filtered_2 = FILTER filtered_1  BY field4 >= 50;


All you are doing in this statement is an AND operation 

filtered_3 = FILTER A BY field3 >= 10 AND field4 >= 50;

Now
grouped = GROUP filtered_3 BY field1;
B = FOREACH grouped GENERATE group as field1, SUM(filtered_3.field3)/SUM(filtered_3.field4) AS A_avg;

apache pig中的总和：错误1045

1 个答案: