G select * from t; (before rewrites) cluster0 Box0:Select cluster1 Box1:BaseTable T boxhead0 Distinct: Preserve 0: Q0.c0 as F1 1: Q0.c1 as F2 2: Q0.c2 as F3 Q0 Q0(F) as T boxhead1 Distinct: Preserve 0: c0 as F1 1: c1 as F2 2: c2 as F3 Q0->boxhead1