开窗函数(javaAPI)

package SparkSQL.fun
 
import org.apache.spark.SparkConf
import org.apache.spark.sql.{Dataset, SparkSession}
 
object PartitionCode {
  def main(args: Array[String]): Unit = {
    val sparkConf = new SparkConf().setAppName("func1").setMaster("local[*]")
    val ss = SparkSession.builder().config(sparkConf).getOrCreate()
    import ss.implicits._
    val dataset:Dataset[(String,String,Int,String)] = ss.createDataset(Array(
      ("zs","c001",21,"男"),
      ("ls","c001",22,"女"),
      ("ww","c001",23,"男"),
      ("ml","c002",20,"女"),
      ("zb","c002",23,"男")
    ))
    dataset.createTempView("student")
 
    /**
     * 查询表中的所有数据，并且每一个人后面跟上班级的平均年龄和总年龄
     *("zs","c001",21,"男"，20，200),
      ("ls","c001",22,"女"，20，200),
      ("ww","c001",23,"男"),
      ("ml","c002",20,"女"),
      ("zb","c002",23,"男")
     */
    val frame = ss.sql("select *, avg(_3) over(partition by _2) avg, sum(_3) over(partition by _2) sum from student")
    frame.show()
    println("-------------------------------")
 
    val frame1 = ss.sql("select *, max(_3) over(partition by _2) max_age from student")
    frame1.show()
 
    ss.stop()
  }
}