pmmag opened a new issue, #17821:
URL: https://github.com/apache/druid/issues/17821
### Affected Version
31.0.0 (have not tried with 32.0.0 yet)
### Description
The following error is produced when running a groupBy query where
`context.vectorize=true` and the grouping dimension is a virtual column of the
form `nvl(col1, col2)` where `col1` exists in at least some segments and `col2`
does not exist in all segments:
```
{
"error": "Unknown exception",
"errorClass": "java.lang.RuntimeException",
"host": "...",
"errorCode": "legacyQueryException",
"persona": "OPERATOR",
"category": "RUNTIME_FAILURE",
"errorMessage": "java.util.concurrent.ExecutionException:
java.lang.ClassCastException",
"context": {
"host": "...",
"errorClass": "java.lang.RuntimeException",
"legacyErrorCode": "Unknown exception"
}
}
```
Logs do not seem to offer much help:
```
2025-03-19T11:19:51,063 ERROR [processing-5]
org.apache.druid.query.groupby.epinephelinae.GroupByMergingQueryRunner -
Exception with one of the sequences!
java.lang.ClassCastException: null
org.apache.druid.query.QueryException:
java.util.concurrent.ExecutionException: java.lang.ClassCastException
at
jdk.internal.reflect.GeneratedConstructorAccessor132.newInstance(Unknown
Source) ~[?:?]
at
java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
~[?:?]
at
java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
~[?:?]
at
java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) ~[?:?]
at
com.fasterxml.jackson.databind.introspect.AnnotatedConstructor.call(AnnotatedConstructor.java:124)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromObjectWith(StdValueInstantiator.java:291)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.ValueInstantiator.createFromObjectWith(ValueInstantiator.java:288)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.impl.PropertyBasedCreator.build(PropertyBasedCreator.java:202)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:455)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.std.ThrowableDeserializer.deserializeFromObject(ThrowableDeserializer.java:65)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:196)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:322)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.ObjectMapper._readValue(ObjectMapper.java:4569)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2798)
~[jackson-databind-2.12.7.1.jar:2.12.7.1]
at
org.apache.druid.client.JsonParserIterator.init(JsonParserIterator.java:196)
[druid-server-31.0.0.jar:31.0.0]
at
org.apache.druid.client.JsonParserIterator.hasNext(JsonParserIterator.java:102)
[druid-server-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.BaseSequence.toYielder(BaseSequence.java:70)
[druid-processing-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.MappedSequence.toYielder(MappedSequence.java:49)
[druid-processing-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$ResultBatch.fromSequence(ParallelMergeCombiningSequence.java:932)
[druid-processing-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$SequenceBatcher.block(ParallelMergeCombiningSequence.java:984)
[druid-processing-31.0.0.jar:31.0.0]
at
java.base/java.util.concurrent.ForkJoinPool.compensatedBlock(ForkJoinPool.java:3451)
[?:?]
at
java.base/java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3434)
[?:?]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$SequenceBatcher.getBatchYielder(ParallelMergeCombiningSequence.java:972)
[druid-processing-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$YielderBatchedResultsCursor.block(ParallelMergeCombiningSequence.java:1107)
[druid-processing-31.0.0.jar:31.0.0]
at
java.base/java.util.concurrent.ForkJoinPool.compensatedBlock(ForkJoinPool.java:3451)
[?:?]
at
java.base/java.util.concurrent.ForkJoinPool.managedBlock(ForkJoinPool.java:3434)
[?:?]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$BatchedResultsCursor.nextBatch(ParallelMergeCombiningSequence.java:1021)
[druid-processing-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$YielderBatchedResultsCursor.initialize(ParallelMergeCombiningSequence.java:1081)
[druid-processing-31.0.0.jar:31.0.0]
at
org.apache.druid.java.util.common.guava.ParallelMergeCombiningSequence$PrepareMergeCombineInputsAction.compute(ParallelMergeCombiningSequence.java:772)
[druid-processing-31.0.0.jar:31.0.0]
at
java.base/java.util.concurrent.RecursiveAction.exec(RecursiveAction.java:194)
[?:?]
at
java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373) [?:?]
at
java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
[?:?]
at
java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655) [?:?]
at
java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
[?:?]
at
java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
[?:?]
```
For context, in our case, we have two datasources, `error-state` and
`help-state`, which contain columns `errorCode` and `helpCode`, respectively,
and the query looks like this (actually it is more complex, this is just a
minimal reproducing example):
```
{
"queryType": "groupBy",
"dataSource": {
"type": "union",
"dataSources": [ "error-state", "help-state" ]
},
"dimensions": [ "code" ],
"granularity": "all",
"virtualColumns": [
{
"type": "expression",
"name": "code",
"expression": "nvl(errorCode, helpCode)",
"outputType": "STRING"
}
],
"intervals": [ "2025-03/2025-04" ],
"context": {"vectorize": true}
}
```
If we change the expression to `nvl(errorCode, nvl(helpCode, ''))` or even
`nvl(errorCode, nvl(helpCode, null))`, the query works as expected (this is our
workaround for now).
The same can be reproduced with any datasource (can be a single table as
well), by grouping on an nvl expression where the second argument is a
reference to a column that doesn't exist in every segment.
This is not a big issue for us because of the workaround, however, we would
expect such queries to either A just work, or B return a useful error message
telling the user if there is something in the query that is not supported.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
