apache-pig - 无法将 org.apache.pig.builtin.SUM 的匹配函数推断为多个或都不适合。请使用显式转换

Question

我想对包含长类型数字的列求和。我尝试了很多可能的方法，但仍然没有解决转换错误。

我的 pig 代码:

raw_ds = LOAD '/tmp/bimallik/data/part-r-00098' using PigStorage(',')  AS (
    d1:chararray, d2:chararray, d3:chararray, d4:chararray, d5:chararray,
    d6:chararray, d7:chararray, d8:chararray, d9:chararray );

parsed_ds = FOREACH raw_ds GENERATE d8  as inBytes:long, d9  as outBytes:long;

X = FOREACH parsed_ds GENERATE (long)SUM(parsed_ds.inBytes) AS inBytes;
dump X;

错误快照:

2015-11-20 02:16:26,631 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1045: Could not infer the matching function for org.apache.pig.builtin.SUM as multiple or none of them fit. Please use an explicit cast. Details at logfile: /users/bimallik/pig_1448014584395.log 2015-11-20 02:17:03,629 [main] INFO org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher - 50% complet

Answer 1

@ManjunathBallur 感谢您的输入。我现在更改了我的代码如下

<..same as before ...>
A = GROUP parsed_ds by inBytes;
X = FOREACH A GENERATE SUM(parsed_ds.inBytes) as h;
DUMP X; 

现在 A 正在生成一包常见的 inBytes，X 给出每个包的 inBytes 总和的总和，它再次由多行组成，因为我需要一个单一的总和值。