Question

我正在尝试从RDD创建数据集。这是我的代码：

class NameOfClass
{
    protected $table = "includes";

}

当我编译上面时，它抛出了以下错误：元组29的元素太多，允许22 Scala版本2.11.11 Spark版本2.2.0

Answer 1

您可以创建case class（您可以将data type更改为您的要求）

case class dataset(col1: Int, col2: Int, col3: Int, col4: Int, col5: Int, col6: Int, col7: Int, col8: Int, col9: Int, col10: Int, col11: Int, col12: Int, col13: Int, col14: Int, col15: Int, col16: Int, col17: Int, col18: Int, col19: Int, col20: Int, col21: Int, col22: Int, col23: Int, col24: Int, col25: Int, col26: Int, col27: Int, col28: Int, col29: Int, col30: Int, col31: Int, col32: Int, col33: Int, col34: Int, col35: Int, col36: Int, col37: Int)

并在代码中使用case class。

我将创建用于测试目的的临时字符串，并在代码中创建split字符串，最后使用case class。

val item = "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37"
val s=item.split(",").map(_.toInt)
Seq(dataset(s(0),s(1),s(2),s(3),s(4),s(5),s(6),s(7),s(8),s(9),s(10),s(11),s(12),s(13),s(14),s(15),s(16),s(17),s(18),s(19),s(20),s(21),s(22),s(23),s(24),s(25),s(26),s(27),s(28),s(29),s(30),s(31),s(32),s(33),s(34),s(35),s(36))).toDS().show

这应该为您dataset提供37列

+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|col1|col2|col3|col4|col5|col6|col7|col8|col9|col10|col11|col12|col13|col14|col15|col16|col17|col18|col19|col20|col21|col22|col23|col24|col25|col26|col27|col28|col29|col30|col31|col32|col33|col34|col35|col36|col37|
+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|   1|   2|   3|   4|   5|   6|   7|   8|   9|   10|   11|   12|   13|   14|   15|   16|   17|   18|   19|   20|   21|   22|   23|   24|   25|   26|   27|   28|   29|   30|   31|   32|   33|   34|   35|   36|   37|
+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+

您可以更改案例类和实现以适合您的29列

如何在Spark中创建包含29列的DataSet

1 个答案: