Spark DataFrame添加一列单调递增的id列

import org.apache.spark.sql.functions._
val newDataFrame = dataFrame.withColumn("id", monotonically_increasing_id)

这样只能添加id列，不能单调递增

import org.apache.spark.sql.expressions.Window
import org.apache.spark.sql.functions.row_number
val w = Window.orderBy("count")
val result = df.withColumn("index", row_number().over(w))

这样可以，从1到​​df.length​​