java - 当我更新 JTable 中的数据库时，我得到多个项目

Question

好的，我做了一个新的更新 Jtable 代码，但它不起作用，你能帮我理解为什么吗？

代码如下:

 private void update(){
        DefaultTableModel modelo = new DefaultTableModel();
        try{
            Connection lig;
            lig = DriverManager.getConnection("jdbc:mysql://localhost/bdteste","root","");
            PreparedStatement inst;
            inst = (PreparedStatement) lig.createStatement();
            ResultSet res;
            res = inst.executeQuery("SELECT * FROM pessoa");
            while(res.next()){
                int id = res.getInt("ID");
                String descriçao = res.getString("Descriçao");
                double montante = res.getDouble("Montante");
                String categoria = res.getString("Categoria_Extrato");
                model.addRow(new Object[]{id, descriçao, montante, categoria});
            }
                    res.close();
        inst.close();
        lig.close();
        }

        catch(SQLException ex){
                JOptionPane.showMessageDialog(null, "Erro na base de dados!");
        }
        recdadostbl.setModel(modelo);
    }

事情是这样的: Me inserting the data Error1

Answer 1

我想我找到了问题的解决方案。当我进入表格面板时，我删除所有表格 model.setRowCount(0);，然后使用此方法再次插入所有新旧数据，

public void updatetbl()
{

   try {
Connection lig;
lig = DriverManager.getConnection("jdbc:mysql://localhost/financas","root","");
Statement inst;
inst = lig.createStatement();
ResultSet res = inst.executeQuery("SELECT * FROM extrato");
    while(res.next()){
    int id = res.getInt("ID");
    String descriçao = res.getString("Descriçao");
    double montante = res.getDouble("Montante");
    String categoria = res.getString("Categoria_Extrato");
    model.addRow(new Object[]{id, descriçao, montante, categoria});

    }

   }
   catch(SQLException ex){
       JOptionPane.showMessageDialog(null,"Base de Dados Indisponivel"+ex );
   }
}