if (!(right.getPipeline() instanceof MRPipeline)) {
throw new CrunchRuntimeException("Map-side join is only supported within a MapReduce context");
}
MRPipeline pipeline = (MRPipeline) right.getPipeline();
pipeline.materialize(right);
// TODO Move necessary logic to MRPipeline so that we can theoretically
// optimize his by running the setup of multiple map-side joins concurrently
pipeline.run();