Hi all:
I have a question when using hive. It's described as follows:
Firstly, I create two table:
CREATE TABLE `roncen_tmp`(
`a` bigint,
`b` bigint,
`c` string);
CREATE EXTERNAL TABLE `ext_roncen`(
`aaa` bigint)
LOCATION 'hdfs://xxx/user/hive/warehouse/roncen_tmp'
You see, the two tables have the same hdfs location, but they have different
schema.
Then:
When I run a sql which includes the two tables, the exception occur.
2016-06-14 10:16:56,807 INFO [main]
org.apache.hadoop.hive.ql.exec.MapJoinOperator: Initializing child 2 MAPJOIN
2016-06-14 10:16:56,807 INFO [main]
org.apache.hadoop.hive.ql.exec.MapJoinOperator: Initializing Self MAPJOIN[2]
2016-06-14 10:16:56,815 ERROR [main]
org.apache.hadoop.hive.ql.exec.HashTableDummyOperator: Generating output obj
inspector from dummy object error java.lang.RuntimeException: cannot find field
aaa from [0:a, 1:b, 2:c] at
org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorUtils.getStandardStructFieldRef(ObjectInspectorUtils.java:410)
at
org.apache.hadoop.hive.serde2.BaseStructObjectInspector.getStructFieldRef(BaseStructObjectInspector.java:133)
at
org.apache.hadoop.hive.ql.exec.ExprNodeColumnEvaluator.initialize(ExprNodeColumnEvaluator.java:55)
at
org.apache.hadoop.hive.ql.exec.JoinUtil.getObjectInspectorsFromEvaluators(JoinUtil.java:68)
at
org.apache.hadoop.hive.ql.exec.AbstractMapJoinOperator.initializeOp(AbstractMapJoinOperator.java:68)
at
org.apache.hadoop.hive.ql.exec.MapJoinOperator.initializeOp(MapJoinOperator.java:95)
at
org.apache.hadoop.hive.ql.exec.Operator.initialize(Operator.java:385) at
org.apache.hadoop.hive.ql.exec.Operator.initialize(Operator.java:469) at
org.apache.hadoop.hive.ql.exec.Operator.initializeChildren(Operator.java:425)
at
org.apache.hadoop.hive.ql.exec.HashTableDummyOperator.initializeOp(HashTableDummyOperator.java:40)
at org.apache.hadoop.hive.ql.exec.Operator.initialize(Operator.java:385)
at
org.apache.hadoop.hive.ql.exec.mr.ExecMapper.configure(ExecMapper.java:144) at
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606) at
org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:106) at
org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:75) at
org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:133)
at org.apache.hadoop.mapred.MapRunner.configure(MapRunner.java:38) at
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606) at
org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:106) at
org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:75) at
org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:133)
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:436) at
org.apache.hadoop.mapred.MapTask.run(MapTask.java:352) at
org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:162) at
java.security.AccessController.doPrivileged(Native Method) at
javax.security.auth.Subject.doAs(Subject.java:415) at
org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1680)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:157)
2016-06-14 10:16:56,820 INFO [main]
org.apache.hadoop.hive.ql.exec.HashTableDummyOperator: Initialization Done 5
HASHTABLEDUMMY 2016-06-14 10:16:56,876 INFO [main]
org.apache.hadoop.hive.ql.log.PerfLogger: <PERFLOG method=LoadHashtable
from=org.apache.hadoop.hive.ql.exec.MapJoinOperator> 2016-06-14 10:16:56,876
FATAL [main] org.apache.hadoop.hive.ql.exec.mr.ExecMapper:
java.lang.NullPointerException at
org.apache.hadoop.hive.ql.exec.MapJoinOperator.loadHashTable(MapJoinOperator.java:189)
at
org.apache.hadoop.hive.ql.exec.MapJoinOperator.cleanUpInputFileChangedOp(MapJoinOperator.java:216)
at
org.apache.hadoop.hive.ql.exec.Operator.cleanUpInputFileChanged(Operator.java:1051)
at
org.apache.hadoop.hive.ql.exec.Operator.cleanUpInputFileChanged(Operator.java:1055)
at
org.apache.hadoop.hive.ql.exec.Operator.cleanUpInputFileChanged(Operator.java:1055)
at
org.apache.hadoop.hive.ql.exec.Operator.cleanUpInputFileChanged(Operator.java:1055)
at org.apache.hadoop.hive.ql.exec.MapOperator.process(MapOperator.java:486)
at org.apache.hadoop.hive.ql.exec.mr.ExecMapper.map(ExecMapper.java:176)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:54) at
org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:440) at
org.apache.hadoop.mapred.MapTask.run(MapTask.java:352) at
org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:162) at
java.security.AccessController.doPrivileged(Native Method) at
javax.security.auth.Subject.doAs(Subject.java:415) at
org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1680)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:157)
I find out the reason is that MapOperator uses the <MapInputPath, MapOpCtx>
to store chema infomation.
When the same location corresponding to different shema, it will only store
the first schema[a,b,c], so it cannot find the column 'aaa'.
Do you guys have any idea about this case?
Best Wishes!
