It seems the CSV Array Reader node is not very deterministic. I have a CSV file (without label) with 12578 rows and 249 columns. It occasionally fails with too short rows (all have the same number of columns) or when checked the allow short lines with extra values (in various lines for the same file). There was a case, when it created a NullPointerException:
ERROR CSV Array Reader 2:126:118 Execute failed: (“NullPointerException”): null
DEBUG CSV Array Reader 2:126:118 Execute failed: (“NullPointerException”): null
java.lang.NullPointerException
at org.knime.base.node.util.BufferedFileReader.readNextChar(BufferedFileReader.java:263)
at org.knime.base.node.util.BufferedFileReader.read(BufferedFileReader.java:318)
at org.knime.core.util.tokenizer.Tokenizer.getNextChar(Tokenizer.java:487)
at org.knime.core.util.tokenizer.Tokenizer.nextToken(Tokenizer.java:349)
at org.knime.base.node.io.filereader.FileRowIterator.next(FileRowIterator.java:347)
at org.knime.base.node.io.csvreader.CSVArrayReaderNodeModel2.execute(CSVArrayReaderNodeModel2.java:104)
at org.knime.core.node.NodeModel.execute(NodeModel.java:733)
at org.knime.core.node.NodeModel.executeModel(NodeModel.java:567)
at org.knime.core.node.Node.invokeFullyNodeModelExecute(Node.java:1177)
at org.knime.core.node.Node.execute(Node.java:964)
at org.knime.core.node.workflow.NativeNodeContainer.performExecuteNode(NativeNodeContainer.java:561)
at org.knime.core.node.exec.LocalNodeExecutionJob.mainExecute(LocalNodeExecutionJob.java:95)
at org.knime.core.node.workflow.NodeExecutionJob.internalRun(NodeExecutionJob.java:179)
at org.knime.core.node.workflow.NodeExecutionJob.run(NodeExecutionJob.java:110)
at org.knime.core.util.ThreadUtils$RunnableWithContextImpl.runWithContext(ThreadUtils.java:328)
at org.knime.core.util.ThreadUtils$RunnableWithContext.run(ThreadUtils.java:204)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.knime.core.util.ThreadPool$MyFuture.run(ThreadPool.java:123)
at org.knime.core.util.ThreadPool$Worker.run(ThreadPool.java:246)