[
https://issues.apache.org/jira/browse/HIVE-4329?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Sean Busbey updated HIVE-4329:
--
Description:
Attempting to write to a HCatalog defined table backed by the AvroSerde fails
with the following stacktrace:
{code}
java.lang.ClassCastException: org.apache.hadoop.io.NullWritable cannot be cast
to org.apache.hadoop.io.LongWritable
at
org.apache.hadoop.hive.ql.io.avro.AvroContainerOutputFormat$1.write(AvroContainerOutputFormat.java:84)
at
org.apache.hcatalog.mapreduce.FileRecordWriterContainer.write(FileRecordWriterContainer.java:253)
at
org.apache.hcatalog.mapreduce.FileRecordWriterContainer.write(FileRecordWriterContainer.java:53)
at
org.apache.hcatalog.pig.HCatBaseStorer.putNext(HCatBaseStorer.java:242)
at org.apache.hcatalog.pig.HCatStorer.putNext(HCatStorer.java:52)
at
org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigOutputFormat$PigRecordWriter.write(PigOutputFormat.java:139)
at
org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigOutputFormat$PigRecordWriter.write(PigOutputFormat.java:98)
at
org.apache.hadoop.mapred.MapTask$NewDirectOutputCollector.write(MapTask.java:559)
at
org.apache.hadoop.mapreduce.task.TaskInputOutputContextImpl.write(TaskInputOutputContextImpl.java:85)
{code}
The proximal cause of this failure is that the AvroContainerOutputFormat's
signature mandates a LongWritable key and HCat's FileRecordWriterContainer
forces a NullWritable. I'm not sure of a general fix, other than redefining
HiveOutputFormat to mandate a WritableComparable.
It looks like accepting WritableComparable is what's done in the other Hive
OutputFormats, and there's no reason AvroContainerOutputFormat couldn't also be
changed, since it's ignoring the key. That way fixing things so
FileRecordWriterContainer can always use NullWritable could get spun into a
different issue?
The underlying cause for failure to write to AvroSerde tables is that
AvroContainerOutputFormat doesn't meaningfully implement getRecordWriter, so
fixing the above will just push the failure into the placeholder RecordWriter.
was:
Attempting to write to a HCatalog defined table backed by the AvroSerde fails
with the following stacktrace:
{code}
java.lang.ClassCastException: org.apache.hadoop.io.NullWritable cannot be cast
to org.apache.hadoop.io.LongWritable
at
org.apache.hadoop.hive.ql.io.avro.AvroContainerOutputFormat$1.write(AvroContainerOutputFormat.java:84)
at
org.apache.hcatalog.mapreduce.FileRecordWriterContainer.write(FileRecordWriterContainer.java:253)
at
org.apache.hcatalog.mapreduce.FileRecordWriterContainer.write(FileRecordWriterContainer.java:53)
at
org.apache.hcatalog.pig.HCatBaseStorer.putNext(HCatBaseStorer.java:242)
at org.apache.hcatalog.pig.HCatStorer.putNext(HCatStorer.java:52)
at
org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigOutputFormat$PigRecordWriter.write(PigOutputFormat.java:139)
at
org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigOutputFormat$PigRecordWriter.write(PigOutputFormat.java:98)
at
org.apache.hadoop.mapred.MapTask$NewDirectOutputCollector.write(MapTask.java:559)
at
org.apache.hadoop.mapreduce.task.TaskInputOutputContextImpl.write(TaskInputOutputContextImpl.java:85)
{code}
The proximal cause of this failure is that the AvroContainerOutputFormat's
signature mandates a LongWritable key and HCat's FileRecordWriterContainer
forces a NullWritable. I'm not sure of a general fix, other than redefining
HiveOutputFormat to mandate a WritableComparable.
It looks like accepting WritableComparable is what's done in the other Hive
OutputFormats, and there's no reason AvroContainerOutputFormat couldn't also be
changed, since it's ignoring the key. That way fixing things so
FileRecordWriterContainer can always use NullWritable could get spun into a
different issue?
The underlying issue is that AvroContainerOutputFormat doesn't meaningfully
implement getRecordWriter, so fixing the above will just push the failure into
the placeholder RecordWriter.
> HCatalog clients can't write to AvroSerde backed tables
> ---
>
> Key: HIVE-4329
> URL: https://issues.apache.org/jira/browse/HIVE-4329
> Project: Hive
> Issue Type: Bug
> Components: HCatalog, Serializers/Deserializers
>Affects Versions: 0.10.0
> Environment: discovered in Pig, but it looks like the root cause
> impacts all non-Hive users
>Reporter: Sean Busbey
>
> Attempting to write to a HCatalog defined table backed by the AvroSerde fails
> with the following stacktrace:
> {code}
> java.lang.ClassCastException: org.apache.hadoop.io.NullWritable cannot be
> cast to org.apache.hadoo