我有一个pyflink作业，它读取csv文件（在路径中） data.txt )，将前2个整数列相加，然后打印结果。
这是data.txt文件。

> cat data.txt
1   1   1   1
2   2   2   2

这是文件（名为 batch-prediction.py )负责pyflink的工作。

from pyflink.datastream import StreamExecutionEnvironment
from pyflink.table import *
from pyflink.table.udf import udf

# Load model

# Define UDF

@udf(result_type=DataTypes.INT())
def add(i, j):
  return i + j

settings = EnvironmentSettings.new_instance().use_blink_planner().build()
exec_env = StreamExecutionEnvironment.get_execution_environment()
t_env = StreamTableEnvironment.create(exec_env, environment_settings=settings)

t_env.create_temporary_function("add", add)

SOURCE_DDL = """
CREATE TABLE source (
    user_id INT,
    movie_id INT,
    rating TINYINT,
    event_ms BIGINT
) WITH (
    'connector' = 'filesystem',
    'format' = 'csv',
    'csv.field-delimiter' = '\t',
    'path' = 'data.txt'
)
"""

SINK_DDL = """
CREATE TABLE sink (
    a INT
) WITH (
    'connector' = 'print'
)
"""

t_env.execute_sql(SOURCE_DDL)
t_env.execute_sql(SINK_DDL)
t_env.execute_sql(
    "INSERT INTO sink SELECT add(user_id, movie_id) FROM source"
).wait()

跑步 python batch-prediction.py 很好用。

> python batch-prediction.py
6> +I(2)
5> +I(4)

根据文件：
用户只需在decorator中添加一个额外的参数func\u type=“pandas”。
但是，在添加 func_type="pandas" 在自定义项中，然后运行 python batch-prediction.py 同样，它抛出异常。

Traceback (most recent call last):
  File "batch-prediction.py", line 44, in <module>
    "INSERT INTO sink SELECT add(user_id, movie_id) FROM source"
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/table_result.py", line 76, in wait
    get_method(self._j_table_result, "await")()
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/py4j/java_gateway.py", line 1286, in __call__
    answer, self.gateway_client, self.target_id, self.name)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/util/exceptions.py", line 147, in deco
    return f(*a,**kw)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/py4j/protocol.py", line 328, in get_return_value
    format(target_id, ".", name), value)
py4j.protocol.Py4JJavaError: An error occurred while calling o51.await.
: java.util.concurrent.ExecutionException: org.apache.flink.table.api.TableException: Failed to wait job finish
    at java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)
    at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1908)
    at org.apache.flink.table.api.internal.TableResultImpl.awaitInternal(TableResultImpl.java:119)
    at org.apache.flink.table.api.internal.TableResultImpl.await(TableResultImpl.java:86)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.flink.api.python.shaded.py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
    at org.apache.flink.api.python.shaded.py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
    at org.apache.flink.api.python.shaded.py4j.Gateway.invoke(Gateway.java:282)
    at org.apache.flink.api.python.shaded.py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
    at org.apache.flink.api.python.shaded.py4j.commands.CallCommand.execute(CallCommand.java:79)
    at org.apache.flink.api.python.shaded.py4j.GatewayConnection.run(GatewayConnection.java:238)
    at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.flink.table.api.TableException: Failed to wait job finish
    at org.apache.flink.table.api.internal.InsertResultIterator.hasNext(InsertResultIterator.java:59)
    at org.apache.flink.table.api.internal.TableResultImpl$CloseableRowIteratorWrapper.hasNext(TableResultImpl.java:355)
    at org.apache.flink.table.api.internal.TableResultImpl$CloseableRowIteratorWrapper.isFirstRowReady(TableResultImpl.java:368)
    at org.apache.flink.table.api.internal.TableResultImpl.lambda$awaitInternal$1(TableResultImpl.java:107)
    at java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1640)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    ... 1 more
Caused by: java.util.concurrent.ExecutionException: org.apache.flink.runtime.client.JobExecutionException: Job execution failed.
    at java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)
    at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1908)
    at org.apache.flink.table.api.internal.InsertResultIterator.hasNext(InsertResultIterator.java:57)
    ... 7 more
Caused by: org.apache.flink.runtime.client.JobExecutionException: Job execution failed.
    at org.apache.flink.runtime.jobmaster.JobResult.toJobExecutionResult(JobResult.java:147)
    at org.apache.flink.runtime.minicluster.MiniClusterJobClient.lambda$getJobExecutionResult$2(MiniClusterJobClient.java:119)
    at java.util.concurrent.CompletableFuture.uniApply(CompletableFuture.java:616)
    at java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:591)
    at java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:488)
    at java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:1975)
    at org.apache.flink.runtime.rpc.akka.AkkaInvocationHandler.lambda$invokeRpc$0(AkkaInvocationHandler.java:229)
    at java.util.concurrent.CompletableFuture.uniWhenComplete(CompletableFuture.java:774)
    at java.util.concurrent.CompletableFuture$UniWhenComplete.tryFire(CompletableFuture.java:750)
    at java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:488)
    at java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:1975)
    at org.apache.flink.runtime.concurrent.FutureUtils$1.onComplete(FutureUtils.java:996)
    at akka.dispatch.OnComplete.internal(Future.scala:264)
    at akka.dispatch.OnComplete.internal(Future.scala:261)
    at akka.dispatch.japi$CallbackBridge.apply(Future.scala:191)
    at akka.dispatch.japi$CallbackBridge.apply(Future.scala:188)
    at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:36)
    at org.apache.flink.runtime.concurrent.Executors$DirectExecutionContext.execute(Executors.java:74)
    at scala.concurrent.impl.CallbackRunnable.executeWithValue(Promise.scala:44)
    at scala.concurrent.impl.Promise$DefaultPromise.tryComplete(Promise.scala:252)
    at akka.pattern.PromiseActorRef.$bang(AskSupport.scala:572)
    at akka.pattern.PipeToSupport$PipeableFuture$$anonfun$pipeTo$1.applyOrElse(PipeToSupport.scala:22)
    at akka.pattern.PipeToSupport$PipeableFuture$$anonfun$pipeTo$1.applyOrElse(PipeToSupport.scala:21)
    at scala.concurrent.Future$$anonfun$andThen$1.apply(Future.scala:436)
    at scala.concurrent.Future$$anonfun$andThen$1.apply(Future.scala:435)
    at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:36)
    at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:55)
    at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply$mcV$sp(BatchingExecutor.scala:91)
    at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
    at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
    at scala.concurrent.BlockContext$.withBlockContext(BlockContext.scala:72)
    at akka.dispatch.BatchingExecutor$BlockableBatch.run(BatchingExecutor.scala:90)
    at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:40)
    at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(ForkJoinExecutorConfigurator.scala:44)
    at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
    at akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
    at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
    at akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: org.apache.flink.runtime.JobException: Recovery is suppressed by NoRestartBackoffTimeStrategy
    at org.apache.flink.runtime.executiongraph.failover.flip1.ExecutionFailureHandler.handleFailure(ExecutionFailureHandler.java:116)
    at org.apache.flink.runtime.executiongraph.failover.flip1.ExecutionFailureHandler.getFailureHandlingResult(ExecutionFailureHandler.java:78)
    at org.apache.flink.runtime.scheduler.DefaultScheduler.handleTaskFailure(DefaultScheduler.java:224)
    at org.apache.flink.runtime.scheduler.DefaultScheduler.maybeHandleTaskFailure(DefaultScheduler.java:217)
    at org.apache.flink.runtime.scheduler.DefaultScheduler.updateTaskExecutionStateInternal(DefaultScheduler.java:208)
    at org.apache.flink.runtime.scheduler.SchedulerBase.updateTaskExecutionState(SchedulerBase.java:610)
    at org.apache.flink.runtime.scheduler.SchedulerNG.updateTaskExecutionState(SchedulerNG.java:89)
    at org.apache.flink.runtime.jobmaster.JobMaster.updateTaskExecutionState(JobMaster.java:419)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRpcInvocation(AkkaRpcActor.java:286)
    at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRpcMessage(AkkaRpcActor.java:201)
    at org.apache.flink.runtime.rpc.akka.FencedAkkaRpcActor.handleRpcMessage(FencedAkkaRpcActor.java:74)
    at org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleMessage(AkkaRpcActor.java:154)
    at akka.japi.pf.UnitCaseStatement.apply(CaseStatements.scala:26)
    at akka.japi.pf.UnitCaseStatement.apply(CaseStatements.scala:21)
    at scala.PartialFunction$class.applyOrElse(PartialFunction.scala:123)
    at akka.japi.pf.UnitCaseStatement.applyOrElse(CaseStatements.scala:21)
    at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:170)
    at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:171)
    at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:171)
    at akka.actor.Actor$class.aroundReceive(Actor.scala:517)
    at akka.actor.AbstractActor.aroundReceive(AbstractActor.scala:225)
    at akka.actor.ActorCell.receiveMessage(ActorCell.scala:592)
    at akka.actor.ActorCell.invoke(ActorCell.scala:561)
    at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:258)
    at akka.dispatch.Mailbox.run(Mailbox.scala:225)
    at akka.dispatch.Mailbox.exec(Mailbox.scala:235)
    ... 4 more
Caused by: java.util.concurrent.ExecutionException: org.apache.flink.streaming.runtime.tasks.ExceptionInChainedOperatorException: Could not forward element to next operator
    at java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)
    at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1928)
    at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.quiesceTimeServiceAndCloseOperator(StreamOperatorWrapper.java:161)
    at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.close(StreamOperatorWrapper.java:130)
    at org.apache.flink.streaming.runtime.tasks.OperatorChain.closeOperators(OperatorChain.java:412)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.afterInvoke(StreamTask.java:585)
    at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:547)
    at org.apache.flink.runtime.taskmanager.Task.doRun(Task.java:722)
    at org.apache.flink.runtime.taskmanager.Task.run(Task.java:547)
    at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.flink.streaming.runtime.tasks.ExceptionInChainedOperatorException: Could not forward element to next operator
    at org.apache.flink.streaming.runtime.tasks.ChainingOutput.emitWatermark(ChainingOutput.java:128)
    at org.apache.flink.streaming.api.operators.CountingOutput.emitWatermark(CountingOutput.java:41)
    at org.apache.flink.streaming.api.operators.StreamSourceContexts$ManualWatermarkContext.processAndEmitWatermark(StreamSourceContexts.java:315)
    at org.apache.flink.streaming.api.operators.StreamSourceContexts$WatermarkContext.emitWatermark(StreamSourceContexts.java:425)
    at org.apache.flink.streaming.api.operators.StreamSource.advanceToEndOfEventTime(StreamSource.java:122)
    at org.apache.flink.streaming.api.operators.StreamSource.close(StreamSource.java:132)
    at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.lambda$closeOperator$5(StreamOperatorWrapper.java:205)
    at org.apache.flink.streaming.runtime.tasks.StreamTaskActionExecutor$SynchronizedStreamTaskActionExecutor.runThrowing(StreamTaskActionExecutor.java:92)
    at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.closeOperator(StreamOperatorWrapper.java:203)
    at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.lambda$deferCloseOperatorToMailbox$3(StreamOperatorWrapper.java:177)
    at org.apache.flink.streaming.runtime.tasks.StreamTaskActionExecutor$SynchronizedStreamTaskActionExecutor.runThrowing(StreamTaskActionExecutor.java:92)
    at org.apache.flink.streaming.runtime.tasks.mailbox.Mail.run(Mail.java:78)
    at org.apache.flink.streaming.runtime.tasks.mailbox.MailboxExecutorImpl.tryYield(MailboxExecutorImpl.java:91)
    at org.apache.flink.streaming.runtime.tasks.StreamOperatorWrapper.quiesceTimeServiceAndCloseOperator(StreamOperatorWrapper.java:155)
    ... 7 more
Caused by: java.lang.RuntimeException: Failed to close remote bundle
    at org.apache.flink.streaming.api.runners.python.beam.BeamPythonFunctionRunner.finishBundle(BeamPythonFunctionRunner.java:371)
    at org.apache.flink.streaming.api.runners.python.beam.BeamPythonFunctionRunner.flush(BeamPythonFunctionRunner.java:325)
    at org.apache.flink.streaming.api.operators.python.AbstractPythonFunctionOperator.invokeFinishBundle(AbstractPythonFunctionOperator.java:291)
    at org.apache.flink.table.runtime.operators.python.scalar.arrow.RowDataArrowPythonScalarFunctionOperator.invokeFinishBundle(RowDataArrowPythonScalarFunctionOperator.java:77)
    at org.apache.flink.streaming.api.operators.python.AbstractPythonFunctionOperator.processWatermark(AbstractPythonFunctionOperator.java:206)
    at org.apache.flink.streaming.runtime.tasks.ChainingOutput.emitWatermark(ChainingOutput.java:124)
    ... 20 more
Caused by: java.util.concurrent.ExecutionException: java.lang.RuntimeException: Error received from SDK harness for instruction 1: Traceback (most recent call last):
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 35, in create_array
    return pa.Array.from_pandas(s, mask=s.isnull(), type=t)
  File "pyarrow/array.pxi", line 805, in pyarrow.lib.Array.from_pandas
  File "pyarrow/array.pxi", line 265, in pyarrow.lib.array
  File "pyarrow/array.pxi", line 80, in pyarrow.lib._ndarray_to_array
  File "pyarrow/error.pxi", line 108, in pyarrow.lib.check_status
pyarrow.lib.ArrowTypeError: Did not pass numpy.dtype object

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 253, in _execute
    response = task()
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 310, in <lambda>
    lambda: self.create_worker().do_instruction(request), request)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 480, in do_instruction
    getattr(request, request_type), request.instruction_id)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 515, in process_bundle
    bundle_processor.process_bundle(instruction_id))
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/bundle_processor.py", line 978, in process_bundle
    element.data)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/bundle_processor.py", line 218, in process_encoded
    self.output(decoded_value)
  File "apache_beam/runners/worker/operations.py", line 330, in apache_beam.runners.worker.operations.Operation.output
  File "apache_beam/runners/worker/operations.py", line 332, in apache_beam.runners.worker.operations.Operation.output
  File "apache_beam/runners/worker/operations.py", line 195, in apache_beam.runners.worker.operations.SingletonConsumerSet.receive
  File "pyflink/fn_execution/beam/beam_operations_fast.pyx", line 71, in pyflink.fn_execution.beam.beam_operations_fast.FunctionOperation.process
  File "pyflink/fn_execution/beam/beam_operations_fast.pyx", line 74, in pyflink.fn_execution.beam.beam_operations_fast.FunctionOperation.process
  File "apache_beam/coders/coder_impl.py", line 113, in apache_beam.coders.coder_impl.CoderImpl.encode_to_stream
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/fn_execution/beam/beam_coder_impl_slow.py", line 618, in encode_to_stream
    pandas_to_arrow(self._schema, self._timezone, self._field_types, cols))
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 43, in pandas_to_arrow
    schema.types[i]) for i in range(0, len(schema))]
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 43, in <listcomp>
    schema.types[i]) for i in range(0, len(schema))]
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 39, in create_array
    raise RuntimeError(error_msg % (s.dtype, t), e)
RuntimeError: ('Exception thrown when converting pandas.Series (int32) to pyarrow.Array (int32).', ArrowTypeError('Did not pass numpy.dtype object'))

    at java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)
    at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1908)
    at org.apache.beam.sdk.util.MoreFutures.get(MoreFutures.java:57)
    at org.apache.beam.runners.fnexecution.control.SdkHarnessClient$BundleProcessor$ActiveBundle.close(SdkHarnessClient.java:458)
    at org.apache.beam.runners.fnexecution.control.DefaultJobBundleFactory$SimpleStageBundleFactory$1.close(DefaultJobBundleFactory.java:547)
    at org.apache.flink.streaming.api.runners.python.beam.BeamPythonFunctionRunner.finishBundle(BeamPythonFunctionRunner.java:369)
    ... 25 more
Caused by: java.lang.RuntimeException: Error received from SDK harness for instruction 1: Traceback (most recent call last):
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 35, in create_array
    return pa.Array.from_pandas(s, mask=s.isnull(), type=t)
  File "pyarrow/array.pxi", line 805, in pyarrow.lib.Array.from_pandas
  File "pyarrow/array.pxi", line 265, in pyarrow.lib.array
  File "pyarrow/array.pxi", line 80, in pyarrow.lib._ndarray_to_array
  File "pyarrow/error.pxi", line 108, in pyarrow.lib.check_status
pyarrow.lib.ArrowTypeError: Did not pass numpy.dtype object

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 253, in _execute
    response = task()
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 310, in <lambda>
    lambda: self.create_worker().do_instruction(request), request)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 480, in do_instruction
    getattr(request, request_type), request.instruction_id)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/sdk_worker.py", line 515, in process_bundle
    bundle_processor.process_bundle(instruction_id))
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/bundle_processor.py", line 978, in process_bundle
    element.data)
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/apache_beam/runners/worker/bundle_processor.py", line 218, in process_encoded
    self.output(decoded_value)
  File "apache_beam/runners/worker/operations.py", line 330, in apache_beam.runners.worker.operations.Operation.output
  File "apache_beam/runners/worker/operations.py", line 332, in apache_beam.runners.worker.operations.Operation.output
  File "apache_beam/runners/worker/operations.py", line 195, in apache_beam.runners.worker.operations.SingletonConsumerSet.receive
  File "pyflink/fn_execution/beam/beam_operations_fast.pyx", line 71, in pyflink.fn_execution.beam.beam_operations_fast.FunctionOperation.process
  File "pyflink/fn_execution/beam/beam_operations_fast.pyx", line 74, in pyflink.fn_execution.beam.beam_operations_fast.FunctionOperation.process
  File "apache_beam/coders/coder_impl.py", line 113, in apache_beam.coders.coder_impl.CoderImpl.encode_to_stream
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/fn_execution/beam/beam_coder_impl_slow.py", line 618, in encode_to_stream
    pandas_to_arrow(self._schema, self._timezone, self._field_types, cols))
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 43, in pandas_to_arrow
    schema.types[i]) for i in range(0, len(schema))]
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 43, in <listcomp>
    schema.types[i]) for i in range(0, len(schema))]
  File "/usr/local/anaconda3/envs/flink-ml/lib/python3.7/site-packages/pyflink/table/utils.py", line 39, in create_array
    raise RuntimeError(error_msg % (s.dtype, t), e)
RuntimeError: ('Exception thrown when converting pandas.Series (int32) to pyarrow.Array (int32).', ArrowTypeError('Did not pass numpy.dtype object'))

    at org.apache.beam.runners.fnexecution.control.FnApiControlClient$ResponseStreamObserver.onNext(FnApiControlClient.java:177)
    at org.apache.beam.runners.fnexecution.control.FnApiControlClient$ResponseStreamObserver.onNext(FnApiControlClient.java:157)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.stub.ServerCalls$StreamingServerCallHandler$StreamingServerCallListener.onMessage(ServerCalls.java:251)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.ForwardingServerCallListener.onMessage(ForwardingServerCallListener.java:33)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.Contexts$ContextualizedServerCallListener.onMessage(Contexts.java:76)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.internal.ServerCallImpl$ServerStreamListenerImpl.messagesAvailableInternal(ServerCallImpl.java:309)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.internal.ServerCallImpl$ServerStreamListenerImpl.messagesAvailable(ServerCallImpl.java:292)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.internal.ServerImpl$JumpToApplicationThreadServerStreamListener$1MessagesAvailable.runInContext(ServerImpl.java:782)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.internal.ContextRunnable.run(ContextRunnable.java:37)
    at org.apache.beam.vendor.grpc.v1p26p0.io.grpc.internal.SerializingExecutor.run(SerializingExecutor.java:123)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    ... 1 more

库版本：
Apache·Flink==1.12.0
Pandas==0.25.3（通过apache flink安装）
Y箭头==0.17.1
我想知道为什么？