Hive/HivePlugins - Hadoop Wiki

creating custom UDFs First, you need to create a new class that extends UDF, with one or more methods named evaluate. package com.example.hive.udf; import org.apache.hadoop.hive.ql.exec.UDF; import org.apache.hadoop.io.Text; public final class Lower extends UDF { public Text evaluate(final Text s) { if (s == null) { return null; } return new Text(s.toString().toLowerCase()); } }(Note that there's