spark-joining-datasets

spark-join.scala

scala> val left = Seq((0), (1)).toDF("id")
left: org.apache.spark.sql.DataFrame = [id: int]

scala> left.join(right, "id").show
+---+-----+
| id|right|
+---+-----+
|  0| zero|
|  0| four|
+---+-----+


scala> val left = Seq((0), (1)).toDF("id")
left: org.apache.spark.sql.DataFrame = [id: int]

scala> val right = Seq((0, "zero"), (2, "two"), (3, "three"), (0, "four")).toDF("id", "right")
right: org.apache.spark.sql.DataFrame = [id: int, right: string]

scala> left.join(right, "id").show
+---+-----+
| id|right|
+---+-----+
|  0| zero|
|  0| four|
+---+-----+


scala>