java.lang.ClassNotFoundException：com.mysql.jdbc.Driver在Amazon EMR上的Jupyter Notebook中

Question

[尝试从EMR Jupyter Notebook连接到RDS中的MySql数据库时，我发现以下错误：

使用的代码：

from pyspark.sql import SparkSession
hostname="hostname"
dbname = "mysql"
jdbcPort = 3306
username = "user"
password = "password"
jdbc_url = "jdbc:mysql://{0}:{1}/{2}?user={3}&password={4}".format(hostname,jdbcPort, dbname,username,password)
query = "(select * from framework.File_Columns) as table1"
df1 = spark.read.format('jdbc').options(driver = 'com.mysql.jdbc.Driver',url=jdbc_url, dbtable=query ).load()
df1.show()

错误消息：

调用o89.showString时发生错误。：org.apache.spark.SparkException：由于阶段失败而导致作业中止：阶段0的任务0失败4次，最近一次失败：阶段0.0的任务0.3丢失（TID 3，ip-172-31-37-50.us -west-2.compute.internal，执行程序1）：java.lang.ClassNotFoundException：com.mysql.jdbc.Driver

我已将所需的mysql-connector-java-5.1.47.jar下载到/home/hadoop/mysql-connector-java-5.1.47.jar，并按如下所示更新了Spark配置文件：

spark.master                     yarn

spark.driver.extraClassPath      :/usr/lib/hadoop-lzo/lib/*:/usr/lib/hadoop/hadoop-aws.jar:/usr/share/aws/aws-java-sdk/*:/usr/share/aws/emr/emrfs/conf:/usr/share/aws/emr/emrfs/lib/*:/usr/share/aws/emr/emrfs/auxlib/*:/usr/share/aws/emr/goodies/lib/emr-spark-goodies.jar:/usr/share/aws/emr/security/conf:/usr/share/aws/emr/security/lib/*:/usr/share/aws/hmclient/lib/aws-glue-datacatalog-spark-client.jar:/usr/share/java/Hive-JSON-Serde/hive-openx-serde.jar:/usr/share/aws/sagemaker-spark-sdk/lib/sagemaker-spark-sdk.jar:/home/hadoop/extrajars/*:/home/hadoop/extrajars/mysql-connector-java-5.1.47.jar

spark.driver.extraLibraryPath    /usr/lib/hadoop/lib/native:/usr/lib/hadoop-lzo/lib/native:/home/hadoop/extrajars/*:/home/hadoop/extrajars/mysql-connector-java-5.1.47.jar

spark.executor.extraClassPath    :/usr/lib/hadoop-lzo/lib/*:/usr/lib/hadoop/hadoop-aws.jar:/usr/share/aws/aws-java-sdk/*:/usr/share/aws/emr/emrfs/conf:/usr/share/aws/emr/emrfs/lib/*:/usr/share/aws/emr/emrfs/auxlib/*:/usr/share/aws/emr/goodies/lib/emr-spark-goodies.jar:/usr/share/aws/emr/security/conf:/usr/share/aws/emr/security/lib/*:/usr/share/aws/hmclient/lib/aws-glue-datacatalog-spark-client.jar:/usr/share/java/Hive-JSON-Serde/hive-openx-serde.jar:/usr/share/aws/sagemaker-spark-sdk/lib/sagemaker-spark-sdk.jar:/home/hadoop/extrajars/*:/home/hadoop/extrajars/mysql-connector-java-5.1.47.jar

spark.executor.extraLibraryPath  /usr/lib/hadoop/lib/native:/usr/lib/hadoop-lzo/lib/native:/home/hadoop/extrajars/*:/home/hadoop/extrajars/mysql-connector-java-5.1.47.jar

还有什么要做的事情，以便从Jupyter Notebook连接到MySql DB？

Answer 1

由于从Jupyter Notebook运行驱动程序时无法找到驱动程序类，因此可以避免将mysql-connector-java-5.1.47.jar复制到$SPARK_HOME/jars文件夹中进行尝试。根据我的个人经验，它将解决您的驱动程序问题。