使用EMR中的spark ad scala从redshift加载数据

Question

我正在尝试使用EMR集群中齐柏林飞艇中的scala将使用spark的redshift与scala连接起来，我使用了spark-redshift库，但是它不起作用。我尝试了许多解决方案，但我不知道为什么会出现错误

   val df  = spark.read .format("com.databricks.spark.redshift")
   .option("url", "jdbc:redshift://xx:xx/xxxx?user=xxx&password=xxx")
   .option("tempdir", path)
   .option("query", sql_query) .load() ```


``` java.lang.ClassNotFoundException: Failed to find data source:
com.databricks.spark.redshift. Please find packages at http://spark.apache.org/third-party-projects.html
 at org.apache.spark.sql.execution.datasources.DataSource$.lookupDataSource(DataSource.scala:657)
 at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:194)
 at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:167)
 ... 51 elided
Caused by: java.lang.ClassNotFoundException: com.databricks.spark.redshift.DefaultSource
 at scala.reflect.internal.util.AbstractFileClassLoader.findClass(AbstractFileClassLoader.scala:62)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
 at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$20$$anonfun$apply$12.apply(DataSource.scala:634)
 at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$20$$anonfun$apply$12.apply(DataSource.scala:634)
 at scala.util.Try$.apply(Try.scala:192)
 at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$20.apply(DataSource.scala:634)
 at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$20.apply(DataSource.scala:634)
 at scala.util.Try.orElse(Try.scala:84)
 at org.apache.spark.sql.execution.datasources.DataSource$.lookupDataSource(DataSource.scala:634)
 ... 53 more ```

Should I import something before ? or may be do some configuration

Answer 1

为了在EMR中运行特定模块，必须将这些模块添加到群集中。（它们不会自动出现）

您的错误是说它找不到模块。看一眼https://aws.amazon.com/blogs/big-data/powering-amazon-redshift-analytics-with-apache-spark-and-amazon-machine-learning/