我正在尝试实现以下scala代码,但我得到的错误值是DS并非org.apache.spark.rdd.RDD [String]的成员
我已经在线查看了解决方案,但找不到答案我的代码是
import spark.implicits._ val lines = messages.map(_._2) lines.foreachRDD( rdd =>{ val line = rdd.toDS println("Old Schema") line.show() /* */
依赖项
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-core_2.11</artifactId>
<version>2.4.4</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.kafka/kafka-clients -->
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>2.1.1</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-streaming_2.11</artifactId>
<version>2.1.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-streaming-kafka_2.11</artifactId>
<version>1.6.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-sql_2.11</artifactId>
<version>2.0.0-cloudera1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.apache.spark</groupId>
<artifactId>spark-sql_2.10</artifactId>
<version>1.6.2</version>
</dependency>
</dependencies>
我正在尝试实现以下scala代码,但我得到的错误值是DS并非org.apache.spark.rdd.RDD [String]的成员,我已经在线查看了解决方案,但无法弄清楚...
不确定您在做什么,但是不需要这样做。无需foreachRDD。您需要了解驱动程序与执行程序模式,在何处以及为什么会发生什么。