Question

好的我有这个问题。我需要更新我的数据库上的记录，但由于我的SQL语法，我遇到了麻烦。通过按“更新名称”按钮，弹出2条消息，用户选择表的前一个名称和新名称。但该声明从未执行过，名称也不会改变。我的主要目标是将第1个语句中的id“解析”为变量

String name_1 = "SELECT id FROM consoles WHERE name LIKE ? ";

并在此处添加

String name = "UPDATE consoles SET name = ? WHERE id = ?";

是否可以将我从第一个声明中获得的ID解析为变量？

try
{
    Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/test1?user=me&password=12345");
    String name_1 = "SELECT id FROM consoles WHERE name LIKE ? ";
    String name = "UPDATE consoles SET name = ? WHERE name LIKE ?";
    PreparedStatement psname = conn.prepareStatement(name);
    PreparedStatement psname_1 = conn.prepareStatement(name_1);
    String strin =  JOptionPane.showInputDialog(null,"Previous Name : ");
    String strout = JOptionPane.showInputDialog(null,"New Name : "); 
    psname.setString(1,strin);
    psname.setString(2,"%" +strout+ "%");
    psname_1.setString(1,"%"+strin+"%");
    psname.executeUpdate();
    Statement stmtname = conn.createStatement();
    // show the updated table
    ResultSet rsname = stmtname.executeQuery("SELECT * FROM consoles INNER JOIN hardware ON consoles.id=hardware.id"); 
                     .
                     .
                     .
            ADDING THEM TO A JTABLE
                     .
                     .
                     .

Answer 1

切换参数。

psname.setString(2,"%" +strout+ "%");
psname_1.setString(1,"%"+strin+"%");

应该是

psname.setString(2, "%" + strin + "%");
psname_1.setString(1, strout);

Answer 2

try
{
    Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/test1?user=me&password=12345");
    String name = "UPDATE consoles SET name = ? WHERE name LIKE ?";
    PreparedStatement psname = conn.prepareStatement(name);
    String strin =  JOptionPane.showInputDialog(null,"Previous Name : ");
    String strout = JOptionPane.showInputDialog(null,"New Name : "); 
    psname.setString(1,strout);
    psname.setString(2,"%" +strin+ "%");
   psname.executeUpdate();
    Statement stmtname = conn.createStatement();
    // show the updated table
    ResultSet rsname = stmtname.executeQuery("SELECT * FROM consoles INNER JOIN hardware ON consoles.id=hardware.id"); 
                     .
                     .
                     .
            ADDING THEM TO A JTABLE
                     .
                     .
                     .

使用用户输入更新MySQL上的数据记录

2 个答案: