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When writing a dataframe, pyspark creates the directory, creates a temporary dir that directory, but no files. csv & parquet formats return similar errors. It fails with:

```Py4JJavaError: An error occurred while calling o99.save: org.apache.spark.SparkException: Job aborted.
    at org.apache.spark.sql.errors.QueryExecutionErrors$.jobAbortedError(QueryExecutionErrors.scala:496)
    at org.apache.spark.sql.execution.datasources.FileFormatWriter$.write(FileFormatWriter.scala:251)
    at org.apache.spark.sql.execution.datasources.InsertIntoHadoopFsRelationCommand.run(InsertIntoHadoopFsRelationCommand.scala:186)
    at org.apache.spark.sql.execution.command.DataWritingCommandExec.sideEffectResult$lzycompute(commands.scala:113)
    at org.apache.spark.sql.execution.command.DataWritingCommandExec.sideEffectResult(commands.scala:111)
    at org.apache.spark.sql.execution.command.DataWritingCommandExec.executeCollect(commands.scala:125)
    at org.apache.spark.sql.execution.QueryExecution$$anonfun$eagerlyExecuteCommands$1.$anonfun$applyOrElse$1(QueryExecution.scala:110)
    at org.apache.spark.sql.execution.SQLExecution$.$anonfun$withNewExecutionId$5(SQLExecution.scala:103)
    at org.apache.spark.sql.execution.SQLExecution$.withSQLConfPropagated(SQLExecution.scala:163)
    at org.apache.spark.sql.execution.SQLExecution$.$anonfun$withNewExecutionId$1(SQLExecution.scala:90)
    at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:775)
    at org.apache.spark.sql.execution.SQLExecution$.withNewExecutionId(SQLExecution.scala:64)
    at org.apache.spark.sql.execution.QueryExecution$$anonfun$eagerlyExecuteCommands$1.applyOrElse(QueryExecution.scala:110)
    at org.apache.spark.sql.execution.QueryExecution$$anonfun$eagerlyExecuteCommands$1.applyOrElse(QueryExecution.scala:106)
    at org.apache.spark.sql.catalyst.trees.TreeNode.$anonfun$transformDownWithPruning$1(TreeNode.scala:481)
    at org.apache.spark.sql.catalyst.trees.CurrentOrigin$.withOrigin(TreeNode.scala:82)
    at org.apache.spark.sql.catalyst.trees.TreeNode.transformDownWithPruning(TreeNode.scala:481)
    at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.org$apache$spark$sql$catalyst$plans$logical$AnalysisHelper$$super$transformDownWithPruning(LogicalPlan.scala:30)
    at org.apache.spark.sql.catalyst.plans.logical.AnalysisHelper.transformDownWithPruning(AnalysisHelper.scala:267)
    at org.apache.spark.sql.catalyst.plans.logical.AnalysisHelper.transformDownWithPruning$(AnalysisHelper.scala:263)
    at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.transformDownWithPruning(LogicalPlan.scala:30)
    at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.transformDownWithPruning(LogicalPlan.scala:30)
    at org.apache.spark.sql.catalyst.trees.TreeNode.transformDown(TreeNode.scala:457)
    at org.apache.spark.sql.execution.QueryExecution.eagerlyExecuteCommands(QueryExecution.scala:106)
    at org.apache.spark.sql.execution.QueryExecution.commandExecuted$lzycompute(QueryExecution.scala:93)
    at org.apache.spark.sql.execution.QueryExecution.commandExecuted(QueryExecution.scala:91)
    at org.apache.spark.sql.execution.QueryExecution.assertCommandExecuted(QueryExecution.scala:128)
    at org.apache.spark.sql.DataFrameWriter.runCommand(DataFrameWriter.scala:848)
    at org.apache.spark.sql.DataFrameWriter.saveToV1Source(DataFrameWriter.scala:382)
    at org.apache.spark.sql.DataFrameWriter.saveInternal(DataFrameWriter.scala:355)
    at org.apache.spark.sql.DataFrameWriter.save(DataFrameWriter.scala:239)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
    at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
    at py4j.Gateway.invoke(Gateway.java:282)
    at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
    at py4j.commands.CallCommand.execute(CallCommand.java:79)
    at py4j.ClientServerConnection.waitForCommands(ClientServerConnection.java:182)
    at py4j.ClientServerConnection.run(ClientServerConnection.java:106)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.UnsatisfiedLinkError: org.apache.hadoop.io.nativeio.NativeIO$Windows.access0(Ljava/lang/String;I)Z
    at org.apache.hadoop.io.nativeio.NativeIO$Windows.access0(Native Method)
    at org.apache.hadoop.io.nativeio.NativeIO$Windows.access(NativeIO.java:793)
    at org.apache.hadoop.fs.FileUtil.canRead(FileUtil.java:1215)
    at org.apache.hadoop.fs.FileUtil.list(FileUtil.java:1420)
    at org.apache.hadoop.fs.RawLocalFileSystem.listStatus(RawLocalFileSystem.java:601)
    at org.apache.hadoop.fs.FileSystem.listStatus(FileSystem.java:1972)
    at org.apache.hadoop.fs.FileSystem.listStatus(FileSystem.java:2014)
    at org.apache.hadoop.fs.ChecksumFileSystem.listStatus(ChecksumFileSystem.java:761)
    at org.apache.hadoop.fs.FileSystem.listStatus(FileSystem.java:1972)
    at org.apache.hadoop.fs.FileSystem.listStatus(FileSystem.java:2014)
    at org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter.getAllCommittedTaskPaths(FileOutputCommitter.java:334)
    at org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter.commitJobInternal(FileOutputCommitter.java:404)
    at org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter.commitJob(FileOutputCommitter.java:377)
    at org.apache.parquet.hadoop.ParquetOutputCommitter.commitJob(ParquetOutputCommitter.java:48)
    at org.apache.spark.internal.io.HadoopMapReduceCommitProtocol.commitJob(HadoopMapReduceCommitProtocol.scala:182)
    at org.apache.spark.sql.execution.datasources.FileFormatWriter$.$anonfun$write$20(FileFormatWriter.scala:240)
    at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:23)
    at org.apache.spark.util.Utils$.timeTakenMs(Utils.scala:605)
    at org.apache.spark.sql.execution.datasources.FileFormatWriter$.write(FileFormatWriter.scala:240)
    ... 41 more```

My Code:

output_path = ".data/output/FireIncidents/"

fire_df.write.format("parquet").mode("overwrite").save(output_path)# fails, makes folder but no files.

fire_df.write.parquet(output_path, mode='overwrite') # fails creates folder by no file.

fire_df.write.csv(output_path, mode='overwrite') # fails, makes folder but no files.

fire_df.write.save(output_path,format='parquet') # fails, makes folder but no files.

fire_df.write.format("parquet").saveAsTable("tab1") # fails, makes folder but no files.

fire_df.select("incident_number","call_datetime","incident_address").write.save("namesAndFavColors.parquet") # from the documentation, same effect

df_writer = pyspark.sql.DataFrameWriter(fire_df) df_writer = df_writer.saveAsTable('test', format='parquet', mode='overwrite',path=output_path)

type(fire_df) ==pyspark.sql.dataframe.DataFrame

fire_df.select('incident_number', 'call_datetime','incident_address').show()

|incident_number|       call_datetime|    incident_address|
+---------------+--------------------+--------------------+
|     18-0032836|2018/09/06 12:13:...|  16888 RIVERVIEW ST|
|     19-0019239|2019/06/03 06:46:...| 18469 GREENVIEW AVE|
|     20-0010724|2020/04/05 10:44:...|        2930 CODY ST|

etc.

Docs: <https://spark.apache.org/docs/latest/sql-data-sources-load-save-functions.html

* * *

I've tried all the variations above, multiple formats, more that one version of Hadoop,

HADOOP\_HOME== "c:\\hadoop"

hadoop 3.2.1 and or 3.2.2 (tried both) pyspark 3.2.0

Similar SO question, without resolution. [pyspark creates output file as folder](https://stackoverflow.com/questions/49216681/pyspark-creates-output-file-as-folder) (note the comment where the requestor notes that created dir is empty.)

## Answers

It looks like windows native IO libraries is absent.

> Hadoop requires native libraries on Windows to work properly -that includes to access the file:// filesystem, where Hadoop uses some Windows APIs to implement posix-like file access permissions.
> 
> This is implemented in HADOOP.DLL and WINUTILS.EXE
> 
> In particular, %HADOOP\_HOME%\\BIN\\WINUTILS.EXE must be locatable.
> 
> If it is not, Hadoop or an application built on top of Hadoop will fail.

See [https://cwiki.apache.org/confluence/display/HADOOP2/WindowsProblems](https://cwiki.apache.org/confluence/display/HADOOP2/WindowsProblems)

And [winutils repo](https://github.com/cdarlint/winutils)