PyCharm - 当连接到oracle DB时，无法找到驱动程序错误。

Question

我已经在我的Mac上安装了Apache Spark (spark-2.4.5-bin-hadoop2.7 ) 。

/Users/xxxx/Software/

此外, 我下载了ojdbc6.jar在下面的路径。

/Users/xxxx/Software/spark/jars

以下是我在环境变量中做的更新。

export SPARK_HOME=/Users/xxxx/Software/spark
export SPARK_CLASSPATH=/Users/xxxx/spark_env/ojdbc6.jar
export PATH=$PATH:$SPARK_HOME/bin:$SPARK_HOME/sbin
alias python='python3'
export PYSPARK_PYTHON=python3

在终端，我调用了pyspark，并运行了下面的命令，工作正常。

conn_url = "jdbc:oracle:thin:@//xxx.xxx.xxx.xx:1521/USER”
 df = spark.read.format("jdbc").option("url",conn_url).option("drive","oracle.jdbc.driver.OracleDriver").option("dbtable”,”table_name”).option("user”,”xxxx”).option("password”,”xxxx”).load()

我成功地查询了数据库。

现在，我正尝试着用PYCHARM做类似的编程。

PyCharm配置：在Preferences->Project Structure中，我添加了如下内容根。

/Users/xxxx/Software/spark/jars/ojdbc6.jar
Users/xxxx/Software/spark-2.4.5-bin-hadoop2.7/python/lib/py4j-0.10.7-src.zip 
/Users/xxxx/Software/spark-2.4.5-bin-hadoop2.7/python/lib/pyspark.zip 

然后当我运行 "main.py"（其中有连接和查询DB的代码）时，我得到了下面的错误。

Status: FailureError: An error occurred while calling o71.load.
: java.sql.SQLException: No suitable driver
    at java.sql/java.sql.DriverManager.getDriver(DriverManager.java:298)
    at org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions$$anonfun$6.apply(JDBCOptions.scala:105)
    at org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions$$anonfun$6.apply(JDBCOptions.scala:105)
    at scala.Option.getOrElse(Option.scala:121)
    at org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions.<init>(JDBCOptions.scala:104)
    at org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions.<init>(JDBCOptions.scala:35)
    at org.apache.spark.sql.execution.datasources.jdbc.JdbcRelationProvider.createRelation(JdbcRelationProvider.scala:32)
    at org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:318)
    at org.apache.spark.sql.DataFrameReader.loadV1Source(DataFrameReader.scala:223)
    at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:211)
    at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:167)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:567)
    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.GatewayConnection.run(GatewayConnection.java:238)
    at java.base/java.lang.Thread.run(Thread.java:835)

Answer 1

通过添加jar到项目上下文根，它不会工作，因为火花是要寻找该jar在。$SPARK_HOME/jars 文件夹。要做到这一点，有几个选项。

1. 在你的python主脚本中你可以这样定义：os.environ['PYSPARK_SUBMIT_ARGS'] = "--jars file:///<path-to-driver>/ojdbc-<version>.jar pyspark-shell"

2. 把你的驱动程序的jar添加到 $SPARK_HOME/jars 文件夹。