[HIVE-14557] Nullpointer When both SkewJoin and Mapjoin Enabled

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.1.0, 2.1.0
• Fix Version/s: 4.0.0-alpha-1
• Component/s: Physical Optimizer
• Assignee: Rui Li
• Reporter: Nemon Lou
• Created: 17/Aug/16 13:26
• Updated: 17/Nov/22 08:54
• Resolved: 16/Nov/18 11:23

Description

The following sql failed with return code 2 on mr.

create table a(id int,id1 int);
create table b(id int,id1 int);
create table c(id int,id1 int);
set hive.optimize.skewjoin=true;
select a.id,b.id,c.id1 from a,b,c where a.id=b.id and a.id1=c.id1;

Error log as follows:

2016-08-17 21:13:42,081 INFO [main] org.apache.hadoop.hive.ql.exec.mr.ExecMapper: 
<MAP>Id =0
  <Children>
    <TS>Id =21
      <Children>
        <MAPJOIN>Id =28
          <Children>
            <FS>Id =16
              <Children>
              <\Children>
              <Parent>Id = 28 null<\Parent>
            <\FS>
          <\Children>
          <Parent>Id = 21 nullId = 33 
        <HASHTABLEDUMMY>Id =33
          <Children>null
          <\Children>
          <Parent><\Parent>
        <\HASHTABLEDUMMY><\Parent>
        <\MAPJOIN>
      <\Children>
      <Parent>Id = 0 null<\Parent>
    <\TS>
  <\Children>
  <Parent><\Parent>
<\MAP>
2016-08-17 21:13:42,084 INFO [main] org.apache.hadoop.hive.ql.exec.TableScanOperator: Initializing operator TS[21]
2016-08-17 21:13:42,084 INFO [main] org.apache.hadoop.hive.ql.exec.mr.ExecMapper: Initializing dummy operator
2016-08-17 21:13:42,086 INFO [main] org.apache.hadoop.hive.ql.exec.MapOperator: DESERIALIZE_ERRORS:0, RECORDS_IN:0, 
2016-08-17 21:13:42,087 ERROR [main] org.apache.hadoop.hive.ql.exec.mr.ExecMapper: Hit error while closing operators - failing tree
2016-08-17 21:13:42,088 WARN [main] org.apache.hadoop.mapred.YarnChild: Exception running child : java.lang.RuntimeException: Hive Runtime Error while closing operators
	at org.apache.hadoop.hive.ql.exec.mr.ExecMapper.close(ExecMapper.java:207)
	at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:61)
	at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:453)
	at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343)
	at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
	at java.security.AccessController.doPrivileged(Native Method)
	at javax.security.auth.Subject.doAs(Subject.java:422)
	at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
	at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Caused by: java.lang.NullPointerException
	at org.apache.hadoop.hive.ql.exec.MapJoinOperator.closeOp(MapJoinOperator.java:474)
	at org.apache.hadoop.hive.ql.exec.Operator.close(Operator.java:682)
	at org.apache.hadoop.hive.ql.exec.Operator.close(Operator.java:696)
	at org.apache.hadoop.hive.ql.exec.Operator.close(Operator.java:696)
	at org.apache.hadoop.hive.ql.exec.mr.ExecMapper.close(ExecMapper.java:189)
	... 8 more

Issue Links

• fixes: HIVE-21111 ConditionalTask cannot be cast to MapRedTask
• is duplicated by: HIVE-20304 When hive.optimize.skewjoin and hive.auto.convert.join are both set to true, and the execution engine is mr, same stage may launch twice due to the wrong generated plan
• is related to: HIVE-9927 MR doesn't produce correct result for runtime_skewjoin_mapjoin_spark