我尝试从mysql数据库中选择一个表格内容到数据帧, 我按照这个步骤将spark与mysql连接起来。
mysql-connector-java-5.0.8-bin.jar
mysql-connector-java-5.0.8-bin.jar
放在路径$SPARK_HOME/bin/mysql-connector-java-5.0.8-bin.jar
但它仍然无法正常工作代码:
from pyspark import SparkContext
from pyspark.sql import SQLContext, Row
sc = SparkContext()
sqlctx = SQLContext(sc)
dataframe_mysql = sqlctx.read.format("jdbc").options(
url="jdbc:mysql://localhost:3306/database",
driver="com.mysql.jdbc.Driver",
dbtable="user",
user="root",
password="").load()
之后我尝试使用cmd将spark与mysql连接起来 使用-jars参数
启动pyspark shell$SPARK_HOME/bin/pyspark –-jars mysql-connector-java-5.0.8-bin.jar
也不行 我不明白为什么使用driver =“com.mysql.jdbc.Driver” 连接到mysql 谁能帮我 提前谢谢
我收到了这个错误
File "C:/Users/kcs/PycharmProjects/Flunky/SparkMySql.py", line 14, in <module>
password="").load()
File "C:\DataScience\python\pyspark\sql\readwriter.py", line 123, in load
return self._df(self._jreader.load())
File "C:\DataScience\python\lib\py4j-0.8.2.1- src.zip\py4j\java_gateway.py", line 538, in __call__
File "C:\DataScience\python\pyspark\sql\utils.py", line 36, in deco
return f(*a, **kw)
File "C:\DataScience\python\lib\py4j-0.8.2.1-src.zip\py4j\protocol.py", line 300, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o24.load.
: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at org.apache.spark.sql.execution.datasources.jdbc.DriverRegistry$.register(DriverRegistry.scala:38)
at org.apache.spark.sql.execution.datasources.jdbc.DefaultSource.createRelation(DefaultSource.scala:41)
at org.apache.spark.sql.execution.datasources.ResolvedDataSource$.apply(ResolvedDataSource.scala:125)
at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:114)
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:231)
at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:379)
at py4j.Gateway.invoke(Gateway.java:259)
at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:133)
at py4j.commands.CallCommand.execute(CallCommand.java:79)
at py4j.GatewayConnection.run(GatewayConnection.java:207)
at java.lang.Thread.run(Unknown Source)
答案 0 :(得分:1)
看看下载下载mysql-connector-java-5.0.8-bin.jar并在你的代码中启动shell $ SPARK_HOME / bin / pyspark --jars mysql-connector-java-5.1.8-bin.jar你的mysql驱动程序版本不一样,所以你可以在修复后检查一下。
答案 1 :(得分:0)
当我使用pyCharm Spark SQL连接MySQL时,运行时出现此错误。
sc = SparkContext(appName="mysqltest")
sqlContext = SQLContext(sc)
df = sqlContext.read.format("jdbc")\
.options(url="jdbc:mysql://localhost:3306/test",
driver="com.mysql.jdbc.Driver", dbtable="user", user="root", password="root")\
.load()
df.show()
sc.stop()
将mysql-connector-java-5.0.8-bin.jar添加到%SPARK_HOME%jars中,解决该错误