HIVE Row_Sequence achieves column auto-Growth

HIVE Row_Sequence achieves column auto-Growth

Package org. rowsequence;

Import org.apache.Hadoop.hive.ql.exe c. Description;
Import org.apache.hadoop.hive.ql.exe c. 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 ';

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