Pig User Defined Functions#
Writing UDF’s using Java#
build.gradle
SampleEval
Using the UDF#
Registering the Jar file#
REGISTER path;
$./pig -x local
grunt> REGISTER '/home/hadoop/pig/pig-demos.jar'
Defining Alias#
DEFINE alias {function | [`command` [input] [output] [ship] [cache] [stderr] ] };
DEFINE sample_eval t5750.pig.SampleEval();
Using the UDF#
grunt> emp_data = LOAD 'hdfs://localhost:9000/pig_data/employee_details.txt' USING PigStorage(',')
as (id:int, name:chararray, age:int, city:chararray);
grunt> Upper_case = FOREACH emp_data GENERATE sample_eval(name);
grunt> Dump Upper_case;