I think it is almost easier to do this with an extra runtime op. Those are
line 20 lines only as well...
Am 07.03.2014 20:58 schrieb "Robert Metzger" <notifications@github.com>:

> In
> stratosphere-java/src/main/java/eu/stratosphere/api/java/operators/JoinOperator.java:
>
> >  		}
> >  		
> >  		@Override
> >  		protected BinaryNodeTranslation translateToDataFlow() {
> > +			// TODO: Runtime support required. Each left tuple may be returned only once.
> > +			// 	     Special exec strategy (runtime + optimizer) based on hash join required.
> > +			// 		 Either no duplicates of right side in HT or left tuples removed from HT after first match.
>
> Can't you implement that using CoGroup?
>
> —
> Reply to this email directly or view it on GitHub<https://github.com/stratosphere/stratosphere/pull/542/files#r10397365>
> .
>