Ah right of course -- perils of typing code without running it! It feels like this is a pretty core operation that should be added to the main RDD API. Do other people not run into this often?
When I'm validating a foreign key join in my cluster I often check to make sure that the foreign keys land on valid values on the referenced table, and the way I do that is checking to see what percentage of the references actually land. On Thu, Jan 23, 2014 at 6:36 PM, Evan R. Sparks <[email protected]>wrote: > Yup (well, with _._1 at the end!) > > > On Thu, Jan 23, 2014 at 5:28 PM, Andrew Ash <[email protected]> wrote: > >> You're thinking like this? >> >> A.map(v => (v,None)).join(B.map(v => (v,None))).map(_._2) >> >> >> On Thu, Jan 23, 2014 at 6:26 PM, Evan R. Sparks <[email protected]>wrote: >> >>> You could map each to an RDD[(String,None)] and do a join. >>> >>> >>> On Thu, Jan 23, 2014 at 5:18 PM, Andrew Ash <[email protected]>wrote: >>> >>>> Hi spark users, >>>> >>>> I recently wanted to calculate the set intersection of two RDDs of >>>> Strings. I couldn't find a .intersection() method in the autocomplete or >>>> in the Scala API docs, so used a little set theory to end up with this: >>>> >>>> lazy val A = ... >>>> lazy val B = ... >>>> A.union(B).subtract(A.subtract(B)).subtract(B.subtract(A)) >>>> >>>> Which feels very cumbersome. >>>> >>>> Does anyone have a more idiomatic way to calculate intersection? >>>> >>>> Thanks! >>>> Andrew >>>> >>> >>> >> >
