table t1 : {A : int, B : string, C : float} table t2 : {A : float, D : int} datatype list a = Nil | Cons of a * list a val q1 = (SELECT * FROM t1) val r1 : transaction (list {A : int, B : string, C : float}) = query q1 (fn fs _ acc => return (Cons (fs.T1, acc))) Nil val r2 : transaction int = ls <- r1; return (case ls of Nil => 0 | Cons ({A = a, ...}, _) => a)