验证一下spark Row getAS类型以及控制问题

package com.javartisan.demo

import org.apache.spark.sql.SparkSession

object SparkLocal {

  def main(args: Array[String]): Unit = {

    val spark = SparkSession.builder().master("local[*]").appName("spark test").getOrCreate()
    import spark.implicits._

    val sc = spark.sparkContext
    val a: Int = 1
    val b: Int = 1
    val c: String = "1"
    val d: String = "1"

    val arr1 = Array[(Int, Int, String, String)]((a, b, c, d))
    val arr2 = Array[(Int, Int, String, String)]((2, b, c, d))
    val rdd1 = sc.parallelize[(Int, Int, String, String)](arr1)
    val rdd2 = sc.parallelize[(Int, Int, String, String)](arr2)
    val df1 = rdd1.toDF("a", "b", "c", "d")
    val df2 = rdd2.toDF("a1", "b1", "c1", "d1")
    df1.printSchema()
    df2.printSchema()

    val full = df1.join(df2, $"a" === $"a1", "full")
    val newFull = full.rdd.map(row => {
      //GenericRowWithSchema
      println("row class " + row.getClass)
      row
    })
    println(newFull.count())
    full.show(false)
    println(df1.count())
    println(df2.count())
    spark.stop()
  }
}

  

posted @ 2019-05-30 12:54  bf378  阅读(4463)  评论(0编辑  收藏  举报