[NIFI-6062] ExecuteSQLRecord does not write BLOB/CLOB data properly

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.10.0, 1.9.1
• Component/s: Extensions
• Assignee: Matt Burgess
• Reporter: Matt Burgess
• Created: 20/Feb/19 22:35
• Updated: 12/Mar/19 19:40
• Resolved: 12/Mar/19 17:24

Description

When using ExecuteSQLRecord (at least with an AvroRecordSetWriter) to return columns that contain BLOB/CLOB data, the following error is reported:

org.apache.nifi.processor.exception.ProcessException: java.io.IOException: org.apache.nifi.serialization.record.util.IllegalTypeConversionException: Cannot convert value oracle.sql.BLOB@79c3c046 of type class oracle.sql.BLOB because no compatible types exist in the UNION for field IMAGE
at org.apache.nifi.processors.standard.AbstractExecuteSQL.lambda$onTrigger$1(AbstractExecuteSQL.java:273)
at org.apache.nifi.controller.repository.StandardProcessSession.write(StandardProcessSession.java:2663)
at org.apache.nifi.processors.standard.AbstractExecuteSQL.onTrigger(AbstractExecuteSQL.java:269)
at org.apache.nifi.processor.AbstractProcessor.onTrigger(AbstractProcessor.java:27)
at org.apache.nifi.controller.StandardProcessorNode.onTrigger(StandardProcessorNode.java:1162)
at org.apache.nifi.controller.tasks.ConnectableTask.invoke(ConnectableTask.java:205)
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:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.io.IOException: org.apache.nifi.serialization.record.util.IllegalTypeConversionException: Cannot convert value oracle.sql.BLOB@79c3c046 of type class oracle.sql.BLOB because no compatible types exist in the UNION for field IMAGE
at org.apache.nifi.processors.standard.sql.RecordSqlWriter.writeResultSet(RecordSqlWriter.java:85)
at org.apache.nifi.processors.standard.AbstractExecuteSQL.lambda$onTrigger$1(AbstractExecuteSQL.java:271)
... 13 common frames omitted
Caused by: org.apache.nifi.serialization.record.util.IllegalTypeConversionException: Cannot convert value oracle.sql.BLOB@79c3c046 of type class oracle.sql.BLOB because no compatible types exist in the UNION for field IMAGE
at org.apache.nifi.avro.AvroTypeUtil.convertUnionFieldValue(AvroTypeUtil.java:897)
at org.apache.nifi.avro.AvroTypeUtil.convertToAvroObject(AvroTypeUtil.java:783)
at org.apache.nifi.avro.AvroTypeUtil.createAvroRecord(AvroTypeUtil.java:578)
at org.apache.nifi.avro.AvroTypeUtil.createAvroRecord(AvroTypeUtil.java:561)
at org.apache.nifi.avro.WriteAvroResultWithSchema.writeRecord(WriteAvroResultWithSchema.java:60)
at org.apache.nifi.serialization.AbstractRecordSetWriter.write(AbstractRecordSetWriter.java:59)
at org.apache.nifi.serialization.AbstractRecordSetWriter.write(AbstractRecordSetWriter.java:52)
at org.apache.nifi.processors.standard.sql.RecordSqlWriter.writeResultSet(RecordSqlWriter.java:79)
... 14 common frames omitted

ExecuteSQL does not have this problem as it uses JdbcCommon which has custom BLOB/CLOB logic, where ExecuteSQLRecord uses AvroTypeUtil which does not catch BLOB/CLOB as a special case. The logic should be updated to match JdbcCommon for BLOB/CLOB handling.

Issue Links

• links to: GitHub Pull Request #3329