private void CreateSelectClauseFromFromClause(IASTNode qn)
        {
            // TODO - check this.  Not *exactly* the same logic as the Java original
            qn.InsertChild(0, (IASTNode)adaptor.Create(SELECT_CLAUSE, "{derived select clause}"));

            _selectClause = ( SelectClause )qn.GetChild(0);
            _selectClause.InitializeDerivedSelectClause(_currentFromClause);

            if (log.IsDebugEnabled())
            {
                log.Debug("Derived SELECT clause created.");
            }
        }