Problem Solving in the DISCO Constraint Database System

. This paper describes general approaches to solving two classes of problems using the DISCO constraint database system. The first class of problems occurs when distinct values from a subset of the integers must be assigned to the variables of a constraint satisfaction problem. The second occurs when a group of items must be selected from a subset of the integers such that each of a set of constraints holds. 1 Introduction DISCO [1] is a constraint database system with a unique combination of two features: (1) it can accept (integer and set) constraint databases as inputs and (2) it can find a (constraint) database representation of the whole fixpoint model of each program on any given input database. No other system can do both. Constraint logic programming systems with sets like CLPS [7], Conjuncto [4], ECLIPSE [3], and flogg [2] can do (1) but cannot do (2). Database systems like CORAL [9] and LDL [15] can do (2) but cannot do (1). The unique combination of achieving both (1) and (..