[NIFI-5612] org.apache.avro.UnresolvedUnionException: Not in union ["null","int"]: 0

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.5.0, 1.6.0, 1.7.1
• Fix Version/s: 1.8.0
• Component/s: Extensions
• Labels: ExecuteSQL avro nifi
• Environment: Microsoft Windows, MySQL Enterprise 5.0.80
• Assignee: Unassigned
• Reporter: Colin Dean
• Created: 19/Sep/18 20:13
• Updated: 28/Sep/18 18:33
• Resolved: 28/Sep/18 17:48

Description

I'm seeing this when I execute SELECT * FROM <tablename> on a few tables but not on dozens of others in the same database.

2018-09-13 01:11:31,434 WARN [Timer-Driven Process Thread-8] o.a.n.controller.tasks.ConnectableTask Administratively Yielding ExecuteSQL[id=cf5c0996-eddf-3e05-25a3-c407c5edf990] due to uncaught Exception: org.apache.avro.file.DataFileWriter$AppendWriteException: org.apache.avro.UnresolvedUnionException: Not in union ["null","int"]: 0
org.apache.avro.file.DataFileWriter$AppendWriteException: org.apache.avro.UnresolvedUnionException: Not in union ["null","int"]: 0
	at org.apache.avro.file.DataFileWriter.append(DataFileWriter.java:308)
	at org.apache.nifi.processors.standard.util.JdbcCommon.convertToAvroStream(JdbcCommon.java:462)
	at org.apache.nifi.processors.standard.ExecuteSQL.lambda$onTrigger$1(ExecuteSQL.java:252)
	at org.apache.nifi.controller.repository.StandardProcessSession.write(StandardProcessSession.java:2625)
	at org.apache.nifi.processors.standard.ExecuteSQL.onTrigger(ExecuteSQL.java:242)
	at org.apache.nifi.processor.AbstractProcessor.onTrigger(AbstractProcessor.java:27)
	at org.apache.nifi.controller.StandardProcessorNode.onTrigger(StandardProcessorNode.java:1165)
	at org.apache.nifi.controller.tasks.ConnectableTask.invoke(ConnectableTask.java:203)
	at org.apache.nifi.controller.scheduling.TimerDrivenSchedulingAgent$1.run(TimerDrivenSchedulingAgent.java:117)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.avro.UnresolvedUnionException: Not in union ["null","int"]: 0
	at org.apache.avro.generic.GenericData.resolveUnion(GenericData.java:709)
	at org.apache.avro.generic.GenericDatumWriter.resolveUnion(GenericDatumWriter.java:192)
	at org.apache.avro.generic.GenericDatumWriter.writeWithoutConversion(GenericDatumWriter.java:110)
	at org.apache.avro.generic.GenericDatumWriter.write(GenericDatumWriter.java:73)
	at org.apache.avro.generic.GenericDatumWriter.writeField(GenericDatumWriter.java:153)
	at org.apache.avro.generic.GenericDatumWriter.writeRecord(GenericDatumWriter.java:143)
	at org.apache.avro.generic.GenericDatumWriter.writeWithoutConversion(GenericDatumWriter.java:105)
	at org.apache.avro.generic.GenericDatumWriter.write(GenericDatumWriter.java:73)
	at org.apache.avro.generic.GenericDatumWriter.write(GenericDatumWriter.java:60)
	at org.apache.avro.file.DataFileWriter.append(DataFileWriter.java:302)
	... 15 common frames omitted

I don't know if I can share the database schema – still working with my team on that – but looking at it, I think it has something to do with the signedness of int(1) or tinyint(1) because those two are the only numerical types common to all of the table.

 

Edit 2018-09-24, so that my update doesn't get buried:

I am able to reproduce the exception using

• Vagrant 2.1.1
• Virtualbox 5.2.18 r124319
• Ubuntu 18.04
• MySQL 5.0.81 (as close as I can get to the 5.0.80 Enterprise Edition in use on the system where I observed this failure first)
• MySQL Connector/J 5.1.46
• NiFi 1.7.1

With this table definition and data:

create table fails ( 
  fails int(1) unsigned NOT NULL default '0' 
) ENGINE=InnoDB AUTO_INCREMENT=16527 DEFAULT CHARSET=latin1;

insert into fails values ();

and an ExecuteSQL processor set up to access that table.

Issue Links

• links to: GitHub Pull Request #3032