Looks like you're using Spark 1.6.x What error(s) did you get for the first two joins ?
Thanks On Fri, Apr 8, 2016 at 3:53 AM, JH P <u40...@gmail.com> wrote: > Hi. I want a dataset join with itself. So i tried below codes. > > 1. newGnsDS.joinWith(newGnsDS, $"dataType”) > > 2. newGnsDS.as("a").joinWith(newGnsDS.as("b"), $"a.dataType" === $ > "b.datatype”) > > 3. val a = newGnsDS.map(x => x).as("a") > val b = newGnsDS.map(x => x).as("b") > > > a.joinWith(b, $"a.dataType" === $"b.datatype") > > 1,2 doesn’t work, but 3 works. I don’t know why it works, better idea > exists. please help >