将Spark DataFrame映射转换为`{"Key"：key，"Value"：value}`的映射数组

import org.apache.spark.sql.{DataFrame, Row}
import org.apache.spark.sql.functions._

val rdd = dataframe.rdd
val keyValuePairRDD = rdd.map(row => {
  val key = row.getAs[String]("Key")
  val value = row.getAs[String]("Value")
  (key, value)
})

val resultDataFrame = keyValuePairRDD.toDF("Key", "Value")

import org.apache.spark.sql.{DataFrame, Row}
import org.apache.spark.sql.functions._

// 将Spark DataFrame映射转换为{"Key"：key，"Value"：value}的映射数组
def transformDataFrameToKeyValueArray(dataframe: DataFrame): DataFrame = {
  val rdd = dataframe.rdd
  val keyValuePairRDD = rdd.map(row => {
    val key = row.getAs[String]("Key")
    val value = row.getAs[String]("Value")
    (key, value)
  })
  val resultDataFrame = keyValuePairRDD.toDF("Key", "Value")
  resultDataFrame
}

// 示例数据
val data = Seq(
  ("key1", "value1"),
  ("key2", "value2"),
  ("key3", "value3")
)
val spark = SparkSession.builder().getOrCreate()
val dataframe = spark.createDataFrame(data).toDF("Key", "Value")

// 调用方法进行转换
val result = transformDataFrameToKeyValueArray(dataframe)
result.show()