When you turn "vectorized" on, does the following query consistently return
10000 in the output?
select ten_thousand() from testTabOrc
Yong
Date: Fri, 30 May 2014 08:24:43 -0400
Subject: Vectorization with UDFs returns incorrect results
From: bbowman...@gmail.com
To: user@hive.apache.org
Hive 0.13 & Hadoop 2.4
I am having an issue when using the combination of vectorized query execution,
BETWEEN, and a custom UDF. When I have vectorization on, my query returns an
empty set. When I then turn vectorization off, my query returns the correct
results.
Example Query: SELECT column_1 FROM table_1 WHERE column_1 BETWEEN (UDF_1 - X)
and UDF_1
My UDFs seem to be working for everything else except this specific
circumstance. Is this a issue in the hive software or am I writing my UDFs in
such a way that they do not work with vectorization? If the latter, what is
the correct way?
I created a test scenario where I was able to reproduce this problem I am
seeing:
TEST UDF (SIMPLE FUNCTION THAT TAKES NO ARGUMENTS AND RETURNS 10000):
package com.test;
import org.apache.hadoop.hive.ql.exec.Description;import
org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.io.LongWritable;import
org.apache.hadoop.io.Text;import java.lang.String;
import java.lang.*;
public class tenThousand extends UDF {
private final LongWritable result = new LongWritable();
public LongWritable evaluate() { result.set(10000); return result;
}}
TEST DATA (test.input):1|CBCABC|12
2|DBCABC|133|EBCABC|1440000|ABCABC|1550000|BBCABC|16
60000|CBCABC|17
CREATING ORC TABLE:
0: jdbc:hive2://server:10002/db> create table testTabOrc (first bigint, second
varchar(20), third int) partitioned by (range int) clustered by (first) sorted
by (first) into 8 buckets stored as orc tblproperties ("orc.compress" =
"SNAPPY", "orc.index" = "true");
CREATE LOADING TABLE:0: jdbc:hive2://server:10002/db> create table loadingDir
(first bigint, second varchar(20), third int) partitioned by (range int) row
format delimited fields terminated by '|' stored as textfile;
COPY IN DATA:[root@server]# hadoop fs -copyFromLocal /tmp/test.input
/db/loading/.
ORC DATA:[root@server]# beeline -u jdbc:hive2://server:10002/db -n root
--hiveconf hive.exec.dynamic.partition.mode=nonstrict --hiveconf
hive.enforce.sorting=true -e "insert into table testTabOrc partition(range)
select * from loadingDir;"
LOAD TEST FUNCTION:0: jdbc:hive2://server:10002/db> add jar
/opt/hadoop/lib/testFunction.jar
0: jdbc:hive2://server:10002/db> create temporary function ten_thousand as
'com.test.tenThousand';
TURN OFF VECTORIZATION:0: jdbc:hive2://server:10002/db> set
hive.vectorized.execution.enabled=false;
QUERY (RESULTS AS EXPECTED):0: jdbc:hive2://server:10002/db> select first from
testTabOrc where first between ten_thousand()-10000 and ten_thousand()-9995;
+--------+| first |+--------+
| 1 || 2 || 3 |+--------+
3 rows selected (15.286 seconds)
TURN ON VECTORIZATION:
0: jdbc:hive2://server:10002/db> set hive.vectorized.execution.enabled=true;
QUERY AGAIN (WRONG RESULTS):
0: jdbc:hive2://server:10002/db> select first from testTabOrc where first
between ten_thousand()-10000 and ten_thousand()-9995;
+--------+| first |+--------++--------+
No rows selected (17.763 seconds)
