HIVE Row_Sequence 实现列自增长

package org.rowsequence;import org.apache.hadoop.hive.ql.exec.Description;import org.apache.hadoop.hive.ql.exec.UDF;import org.apache.hadoop.hive.ql.udf.UDFType;import org.apache.hadoop.io.LongWritable;/** * UDFRowSequence. */@Description(name = "row_sequence",    value = "_FUNC_() - Returns a generated row sequence number starting from 1")@UDFType(deterministic = false)public class RowSequence extends UDF {private LongWritable result = new LongWritable();  public RowSequence() {    result.set(0);  }  public LongWritable evaluate() {    result.set(result.get() + 1);    return result;  }}

add jar /home/hadoop/hive_study/hive_udf/hive_udf.jar

create temporary function row_sequence as 'org.rowsequence.RowSequence';