Ranking popularnosci piosenek

 val conf = new SparkConf().setAppName("Simple Application").setMaster("local")
    val sc = new SparkContext(conf)

    val spark = org.apache.spark.sql.SparkSession.builder
      .master("local")
      .appName("Spark CSV Reader")
      .getOrCreate;


    val samples = spark.read.format("com.databricks.spark.csv").
      option("sep",",").
      csv("samples.txt").
      toDF("user_id", "song_id", "date_id")
    val songs = spark.read.format("com.databricks.spark.csv").
      option("sep",",").
      csv("tracks1.txt").
      toDF("track_id","song_id","artist","title","nowe_id")


    samples.groupBy("song_id")
      .count().join(songs,"song_id")
      .select("title","artist","count")
      .orderBy(desc("count"))
      .show(10,false)