public RelNode convert(RelNode rel) { final UncollectRel uncollect = (UncollectRel) rel; final RelTraitSet traitSet = uncollect.getTraitSet().replace(EnumerableConvention.INSTANCE); final RelNode input = uncollect.getChild(); return new EnumerableUncollectRel( rel.getCluster(), traitSet, convert(input, input.getTraitSet().replace(EnumerableConvention.INSTANCE))); } }