I think this was mostly an oversight on my part that was possible because we didn't have good test-coverage that was enforcing correctness. Please go ahead and open an issue for re-adding the throw.
On Wed, 22 Feb 2017 at 13:28 Lin Li <lincoln.8...@gmail.com> wrote: > Thank you for the answer! > > The discussion on FLINK-1023 is very clear to me. I agree with that throws > a TraversableOnceException when the iterator is requested the second time. > > @Aljoscha git history shows you removed the exception-thrown code from > FLINK-1110, would you mind me create an issue and add it back? > > BTW, I had submitted a pr for FLINK-5498 ( > https://github.com/apache/flink/pull/3379), support left/right outer joins > with non-equi-join conditions via coGroup operator with a generated > OuterJoinCoGroupFunction. > But current implementation is not memory safe when do a many-to-one/many > outer join which will copy the opposite side input into an List buffer(This > is not pretty though it follows the guideline, just remember the input data > within a function call). It's a work-around for now, in the long run, I > think we should extend the runtime join operators to support such > non-equi-join conditions. Implementation in TableAPI layer could not > always ensures the efficiency. > Welcome any suggestions on current solution. > > Best, Lincoln >
