HIVE Row_Sequence 实现列自增长

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.jarcreate temporary function row_sequence as "org.rowsequence.RowSequence";Hive 的详细介绍：请点这里
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