去正規化地圖類型

Question

鑑於此集合：

("user1",Map("Gobelin" -> "2","Archers" ->"3")) 
("user2",Map("Giant" -> "1")) 

我想要的輸出看起來像這樣

("user1","Gobelin","2") 
("user1","Archers","3") 
("user2","Giant","1") 

我怎樣才能達致這與火花？

Answer 1

最有可能你正在尋找flatMapValues：

val rdd = sc.parallelize(
    ("user1",Map("Gobelin" -> "2","Archers" ->"3")) :: 
    ("user2",Map("Giant" -> "1")) :: Nil) 

rdd.flatMapValues(identity[Map[String, String]]) 

或explode：

rdd.toDF.select($"_1", explode($"_2")).as[(String, String, String)].rdd