如何在java中使用预处理语句（Prepared Statement）？

解决方法

下面的示例使用prepareStatement方法来创建PreparedStatement。它还使用预处理的setInt和setString方法来设置预处理语句的参数。

import java.sql.*;

public class jdbcConn {
   public static void main(String[] args) throws Exception{
      Class.forName("org.apache.derby.jdbc.ClientDriver");
      Connection con = DriverManager.getConnection
      ("jdbc:derby://localhost:1527/testDb","name","pass");
      PreparedStatement updateemp = con.prepareStatement
      ("insert into emp values(?,?,?)");
      updateemp.setInt(1,23);
      updateemp.setString(2,"Roshan");
      updateemp.setString(3, "CEO");
      updateemp.executeUpdate();
      Statement stmt = con.createStatement();
      String query = "select * from emp";
      ResultSet rs =  stmt.executeQuery(query);
      System.out.println("Id Name    Job");
      while (rs.next()) {
         int id = rs.getInt("id");
         String name = rs.getString("name");
         String job = rs.getString("job");
         System.out.println(id + "  " + name+"   "+job);
      }      
   }
}

结果

上面的代码示例将产生以下结果。该结果可能会不同。

Id Name    Job
23  Roshan   CEO