// requires: constraint.ChildColumns form a key in
        // constraint.ChildTable (actually they should subsume the primary key)
        private void GuaranteeForeignKeyConstraintInCSpace(QueryRewriter childRewriter, QueryRewriter parentRewriter,
                                                           ErrorLog errorLog, ConfigViewGenerator config)
        {
            ViewgenContext childContext  = childRewriter.ViewgenContext;
            ViewgenContext parentContext = parentRewriter.ViewgenContext;
            CellTreeNode   cNode         = childRewriter.BasicView;
            CellTreeNode   pNode         = parentRewriter.BasicView;

            FragmentQueryProcessor qp = FragmentQueryProcessor.Merge(childContext.RightFragmentQP, parentContext.RightFragmentQP);
            bool cImpliesP            = qp.IsContainedIn(cNode.RightFragmentQuery, pNode.RightFragmentQuery);

            if (false == cImpliesP)
            {
                // Foreign key constraint not being ensured in C-space
                string childExtents  = LeftCellWrapper.GetExtentListAsUserString(cNode.GetLeaves());
                string parentExtents = LeftCellWrapper.GetExtentListAsUserString(pNode.GetLeaves());
                string message       = System.Data.Entity.Strings.ViewGen_Foreign_Key_Not_Guaranteed_InCSpace(
                    ToUserString());
                // Add all wrappers into allWrappers
                Set <LeftCellWrapper> allWrappers = new Set <LeftCellWrapper>(pNode.GetLeaves());
                allWrappers.AddRange(cNode.GetLeaves());
                ErrorLog.Record record = new ErrorLog.Record(true, ViewGenErrorCode.ForeignKeyNotGuaranteedInCSpace, message, allWrappers, String.Empty);
                errorLog.AddEntry(record);
            }
        }
        // requires: IsForeignKeySuperSetOfPrimaryKeyInChildTable() is false
        // and primaryKeys of ChildTable are not mapped in cell. cell
        // corresponds to an association set. parentSet is the set
        // corresponding to the end that we are looking at
        // effects: Checks if the constraint is correctly maintained in
        // C-space via an association set (being a subset of the
        // corresponding entitySet)
        private bool CheckConstraintWhenOnlyParentMapped(Cell cell, EntitySet parentSet, AssociationSet assocSet, AssociationEndMember endMember,
                                                         QueryRewriter childRewriter, QueryRewriter parentRewriter,
                                                         ConfigViewGenerator config)
        {
            ViewgenContext childContext  = childRewriter.ViewgenContext;
            ViewgenContext parentContext = parentRewriter.ViewgenContext;

            CellTreeNode pNode = parentRewriter.BasicView;

            Debug.Assert(pNode != null);

            RoleBoolean endRoleBoolean = new RoleBoolean(assocSet.AssociationSetEnds[endMember.Name]);
            // use query in pNode as a factory to create a bool expression for the endRoleBoolean
            BoolExpression endCondition = pNode.RightFragmentQuery.Condition.Create(endRoleBoolean);
            FragmentQuery  cNodeQuery   = FragmentQuery.Create(pNode.RightFragmentQuery.Attributes, endCondition);

            FragmentQueryProcessor qp = FragmentQueryProcessor.Merge(childContext.RightFragmentQP, parentContext.RightFragmentQP);
            bool cImpliesP            = qp.IsContainedIn(cNodeQuery, pNode.RightFragmentQuery);

            return(cImpliesP);
        }