G select f1 from t group by f1 having f1 > 10; (before rewrites) cluster3 Box3:Select cluster2 Box2:Grouping cluster0 Box0:Select cluster1 Box1:BaseTable T boxhead3 Distinct: Preserve 0: Q2.c0 as F1 UNIQUE KEY [0] Q2 Q2(F) Q2->Q2 (Q2.c0) > (10) boxhead2 Distinct: Preserve 0: Q1.c0 as F1 GROUP Q1.c0 Ascending UNIQUE KEY [0] Q2->boxhead2 Q1 Q1(F) boxhead0 Distinct: Preserve 0: Q0.c0 as F1 1: Q0.c1 as F2 2: Q0.c2 as F3 Q1->boxhead0 Q0 Q0(F) as T boxhead1 Distinct: Preserve 0: c0 as F1 1: c1 as F2 2: c2 as F3 Q0->boxhead1