java - JDBC 连接无法从 apache spark 连接 Teradata

Question

我尝试了许多不同的方法来使用 JDBC 连接从 Apache Spark 连接到我们的 Teradata 环境。下面是我一直在使用的代码。

我确保我的 JDBC 驱动程序是正确的，因为我使用相同的驱动程序从其他平台连接到 Teradata。

我还在运行 spark-shell 时添加驱动程序 Jar./bin/spark-shell --jars/home/path/*.jar --driver-class-path/home/path/*.jar

如有任何帮助，我们将不胜感激!

val jdbcDF = sqlContext.load("jdbc", Map(
  "url" -> "jdbc:teradata://<server_name>, TMODE=TERA, user=my_user, password=*****",
  "dbtable" -> "schema.table_name",
  "driver" -> "com.teradata.jdbc.TeraDriver"))

异常的堆栈跟踪:

warning: there were 1 deprecation warning(s); re-run with -deprecation for details
java.lang.ClassNotFoundException: com.teradata.jdbc.TeraDriver
        at scala.tools.nsc.interpreter.AbstractFileClassLoader.findClass(AbstractFileClassLoader.scala:83)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        at org.apache.spark.sql.jdbc.package$DriverRegistry$.register(jdbc.scala:227)
        at org.apache.spark.sql.jdbc.DefaultSource.createRelation(JDBCRelation.scala:94)
        at org.apache.spark.sql.sources.ResolvedDataSource$.apply(ddl.scala:265)
        at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:114)
        at org.apache.spark.sql.SQLContext.load(SQLContext.scala:1242)
        at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:19)
        at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:27)
        at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:29)
        at $iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:31)
        at $iwC$$iwC$$iwC$$iwC.<init>(<console>:33)
        at $iwC$$iwC$$iwC.<init>(<console>:35)
        at $iwC$$iwC.<init>(<console>:37)
        at $iwC.<init>(<console>:39)
        at <init>(<console>:41)
        at .<init>(<console>:45)
        at .<clinit>(<console>)
        at .<init>(<console>:7)
        at .<clinit>(<console>)
        at $print(<console>)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:497)
        at org.apache.spark.repl.SparkIMain$ReadEvalPrint.call(SparkIMain.scala:1065)
        at org.apache.spark.repl.SparkIMain$Request.loadAndRun(SparkIMain.scala:1338)
        at org.apache.spark.repl.SparkIMain.loadAndRunReq$1(SparkIMain.scala:840)
        at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:871)
        at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:819)
        at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:857)
        at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:902)
        at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:875)
        at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:902)
        at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:875)
        at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:902)
        at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:875)
        at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:902)
        at org.apache.spark.repl.SparkILoop.command(SparkILoop.scala:814)
        at org.apache.spark.repl.SparkILoop.processLine$1(SparkILoop.scala:657)
        at org.apache.spark.repl.SparkILoop.innerLoop$1(SparkILoop.scala:665)
        at org.apache.spark.repl.SparkILoop.org$apache$spark$repl$SparkILoop$$loop(SparkILoop.scala:670)
        at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply$mcZ$sp(SparkILoop.scala:997)
        at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply(SparkILoop.scala:945)
        at org.apache.spark.repl.SparkILoop$$anonfun$org$apache$spark$repl$SparkILoop$$process$1.apply(SparkILoop.scala:945)
        at scala.tools.nsc.util.ScalaClassLoader$.savingContextLoader(ScalaClassLoader.scala:135)
        at org.apache.spark.repl.SparkILoop.org$apache$spark$repl$SparkILoop$$process(SparkILoop.scala:945)
        at org.apache.spark.repl.SparkILoop.process(SparkILoop.scala:1059)
        at org.apache.spark.repl.Main$.main(Main.scala:31)
        at org.apache.spark.repl.Main.main(Main.scala)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:497)
        at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:664)
        at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:169)
        at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:192)
        at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:111)
        at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)

Answer 1

我终于搞定了。它不适用于 --jars 的原因在 spark docs 中有解释。 :

The JDBC driver class must be visible to the primordial class loader on the client session and on all executors. This is because Java’s DriverManager class does a security check that results in it ignoring all drivers not visible to the primordial class loader when one goes to open a connection.

解决方法是:

1. 将 JDBC jar 复制到集群中的每个 spark 节点
2. 修改您的 spark-defaults.conf 为您的驱动程序和执行程序添加 extraClassPath 选项

将这些添加到 spark-defaults.conf:

• spark.driver.extraClassPath
  • /usr/lib/tdch/1.4/lib/terajdbc4.jar:/usr/lib/tdch/1.4/lib/tdgssconfig.jar
• spark.executor.extraClassPath
  • /usr/lib/tdch/1.4/lib/terajdbc4.jar:/usr/lib/tdch/1.4/lib/tdgssconfig.jar

如果您使用的是 Ambari，则可以在“Custom spark-defaults”下添加这两个属性，然后重新启动 Spark。