查询JDBC Java

Question

我的java/jdbc代码有问题。

参数索引超出范围（2号中的哪一个参数1）

代码：

   Connection c = null; 
       MySQL MySQL = new MySQL(Host, Port, Database, Username, Password); 
       c = MySQL.open(); 
       Player player = (Player) sender; 
       String zapytanie = "UPDATE `?` SET `tag`=? WHERE `name`='?';"; 
       PreparedStatement ps = c.prepareStatement(zapytanie); 
       ps.setString(1, Tabel); 
       ps.setString(2, red); 
       ps.setString(3, player()); 
       ps.executeUpdate(); //Executes the query 
       ps.close(); //Closes the query 
       c.close(); 

Answer 1

final String zapytanie = "UPDATE " + Table + " SET tag = ? WHERE name = ?"; 

• 没有围绕
• JDBC不需要所需?引号;后任意 SQL语句
个
• 占位?只能用于列的值