主页 / coding / 问题 / 78583582
Accepted
user25439752
Asked: 2024-06-06 05:29:39 +0800 CST

pyspark.sql 读取 csv 文件时出错：警告 FileStreamSink：假设没有元数据目录。在路径中查找元数据目录时出错

  • 772

我从 pyspark.sql 开始，尝试使用 jupyter-notebook 读取一个简单的 csv 文件。请参阅下面的代码

from pyspark.sql import SparkSession

spark = SparkSession \
    .builder \
    .getOrCreate()

data_path = '//Users/myuser/pysparktest/'
utilization_path = data_path + '/utilization.csv'
user_df = spark.read.csv(utilization_path)

但是我收到以下无法解决的错误：

24/06/05 23:14:32 WARN FileStreamSink: Assume no metadata directory. Error while looking for metadata directory in the path: //Users/myuser/pysparktest/utilization.csv.
org.apache.hadoop.fs.UnsupportedFileSystemException: No FileSystem for scheme "null"
    at org.apache.hadoop.fs.FileSystem.getFileSystemClass(FileSystem.java:3443)
    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:3466)
    at org.apache.hadoop.fs.FileSystem.access$300(FileSystem.java:174)
    at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:3574)
    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:3521)
    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:540)
    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:365)
    at org.apache.spark.sql.execution.streaming.FileStreamSink$.hasMetadata(FileStreamSink.scala:53)
    at org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:366)
    at org.apache.spark.sql.DataFrameReader.loadV1Source(DataFrameReader.scala:229)
    at org.apache.spark.sql.DataFrameReader.$anonfun$load$2(DataFrameReader.scala:211)
    at scala.Option.getOrElse(Option.scala:189)
    at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:211)
    at org.apache.spark.sql.DataFrameReader.csv(DataFrameReader.scala:538)
    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 py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
    at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:374)
    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(Thread.java:750)

有人能帮我弄清楚这里缺少什么吗？

谢谢，

我尝试按照本教程安装本机 hadoop 库：

https://medium.com/@GalarnykMichael/install-spark-on-mac-pyspark-453f395f240b#.be80dcqat。

多次尝试卸载和安装spark、pyspark和jupyter。

期待：

能够读取简单的 csv 文件。

csv

1 个回答

  1. Best Answer

    首先，您的路径字符串以两个斜杠开头。然后，您连接 2 个字符串，其中一个以斜杠结尾，第二个以斜杠开头，这会导致您的路径，//Users/myuser/pysparktest//utilization.csv尽管回溯表示它将路径视为//Users/myuser/pysparktest/utilization.csv.但路径应该是这样的：/Users/myuser/pysparktest/utilization.csv

    • 0

相关问题