Pig - ERROR 1045: AVG as multiple or none of them fit. Please use an explicit cast

hadoop mapreduce apache-pig bigdata
user182944 picture user182944 · Jan 30, 2015 · Viewed 7.4k times · Source

I have a comma seperated .txt file, I want to DUMP the AVG age of all Males.

records = LOAD 'file:/home/gautamshaw/Documents/PigDemo_CommaSep.txt' USING PigStorage(',') AS (firstname:chararray,lastname:chararray,age:int,sex:chararray);
filter_by_male = FILTER records BY sex == 'M';
grouped = GROUP filter_by_male ALL;
average_male_age = FOREACH grouped GENERATE AVG(records.age);

I am getting an error in the FOREACH line:

ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1045: 
<line 6, column 44> Could not infer the matching function for org.apache.pig.builtin.AVG as multiple or none of them fit. Please use an explicit cast.

Please advice.

Answer

Sivasakthi Jayaraman picture Sivasakthi Jayaraman · Jan 30, 2015

You should not project records relation it should be filter_by_male relation.

Can you change your script like this?

average_male_age = FOREACH grouped GENERATE AVG(filter_by_male.age);

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