Sounds like: https://issues.apache.org/jira/browse/SPARK-15441, for which a fix is in progress.
Please do keep reporting issues though, these are great! Michael On Fri, May 27, 2016 at 1:01 PM, Tim Gautier <tim.gaut...@gmail.com> wrote: > Is it truly impossible to left join a Dataset[T] on the right if T has any > non-option fields? It seems Spark tries to create Ts with null values in > all fields when left joining, which results in null pointer exceptions. In > fact, I haven't found any other way to get around this issue without making > all fields in T options. Is there any other way? > > Example: > > case class Test(id: Int) > val test1 = Seq(Test(1), Test(2), Test(3)).toDS > val test2 = Seq(Test(2), Test(3), Test(4)).toDS > test1.as("t1").joinWith(test2.as("t2"), $"t1.id" === $"t2.id", > "left_outer").show > >