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我有一些问题executeQuery。我的代码：

try{

        String where ="";
        String set, sqlque; 
        int help ;
        System.out.println("Laczenie z baza danych ");
        Connection conn = DriverManager.getConnection(DB,USER,PASS);
         conn.setAutoCommit(false);
        Statement stmt = conn.createStatement(
                ResultSet.TYPE_SCROLL_SENSITIVE,
                ResultSet.CONCUR_UPDATABLE);       
        Statement new = conn.createStatement(
                 ResultSet.TYPE_SCROLL_SENSITIVE,
                    ResultSet.CONCUR_UPDATABLE); 

        temporary = describe.getSelectedItem().toString()+"";
        if(!Ab.getText().equals("")){where +=" Ab="+"'"+Ab.getText()+"'AND";};
        sqlpytanie="Select ab, product_id from product where describe=?";
        PreparedStatement stm1 = conn.prepareStatement(sqlpytanie);
        stm1.setString(1, temporary);
        ResultSet rs = stm1.executeQuery();
        while(rs.next()){
            System.out.println("In 1 while");
            tmp1 = rs.getString("Ab");      
            tmp = rs.getString("product_id"); 

       }  
        help= Integer.parseInt(tmp1) - Integer.parseInt(Ab.getText());
        set = "Update Product set ab='"+help+"'"+"where product_id="+tmp;
        System.out.println(help);
        System.out.println(set);
        System.out.println(tmp);
        new.executeUpdate(set);
        sqlque="Select prices  from price where product_id=?";

        PreparedStatement stm2 = conn.prepareStatement(sqlque);
        stm2.setString(1, tmp);
        System.out.println(sqlque);
         ResultSet res = stm2.executeQuery();
         System.out.println(res);
         while(res.next()){
                System.out.println("In 2 while");
                prices= res.getString("prices ");

}

         }
         JOptionPane.showMessageDialog(new JFrame()," ab "+ tmp1 + " prices  " + prices);

         //   updateTotal = conn.prepareStatement(updateStatement);

        conn.commit();
        stmt.close();
        new.close();
        conn.close(); 
}

问题在于 second executeQuery，因为没有结果。Java 没有正确执行这个为什么我会false从中得到System.out.println(res.next());？在我的数据库中，一切都很好，它应该显示信息。我究竟做错了什么？

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