如何使用JDBC程序更新ResultSet的内容？

要更新ResultSet的内容，您需要创建一个语句并传递ResultSet类型为updatable，例如：

//创建一个Statement对象
Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_UPDATABLE);

就像getXXX()和setXXX()方法一样，ResultSet接口还提供了用于更新结果集行的方法updateXXX()。

这些方法接受表示要更新的行的索引或列标签的String值的整数值。

请注意，如果您需要更新ResultSet的内容，则表格应具有主键。

阅读更多：MySQL 教程

示例

假设我们有一个名为Employees的表格，其中有5个记录，如下所示：

+----+---------+--------+----------------+
| Id | Name    | Salary | Location       |
+----+---------+--------+----------------+
|  1 | Amit    | 3000   | Hyderabad      |
|  2 | Kalyan  | 4000   | Vishakhapatnam |
|  3 | Renuka  | 6000   | Delhi          |
|  4 | Archana | 9000   | Mumbai         |
|  5 | Sumith  | 11000  | Hyderabad      |
+----+---------+--------+----------------+

以下示例演示如何更新结果集的内容：

import java.sql.*;
public class ResultSetExample {
    public static void main(String[] args) throws Exception {
        //注册驱动程序
        DriverManager.registerDriver(new com.mysql.jdbc.Driver());
        //获取连接
        String mysqlUrl = "jdbc:mysql://localhost/TestDB";
        Connection con = DriverManager.getConnection(mysqlUrl, "root", "密码");
        System.out.println("连接已建立...");
        //创建一个语句对象
        Statement stmt = con.createStatement(
        ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
        //检索数据
        ResultSet rs = stmt.executeQuery("select * from Employees");
        //打印表的内容
        System.out.println("表格内容:");
        printRs(rs);
        //将指针移动到结果集的起始点
        rs.beforeFirst();
        //将每个员工的工资提高5000
        while(rs.next()){
            //按列名检索
            int newSal = rs.getInt("Salary") + 5000;
            rs.updateInt( "Salary", newSal );
            rs.updateRow();
        }
        System.out.println("提高工资后ResultSet的内容");
        printRs(rs);
        //将位置设置为第二行
        rs.beforeFirst();
        rs.absolute(2);
        System.out.println("我们需要删除的记录:");
        System.out.print("编号: " + rs.getInt("id"));
        System.out.print(", 工资: " + rs.getInt("Salary"));
        System.out.print(", 姓名: " + rs.getString("Name"));
        System.out.println(", 地址: " + rs.getString("Location"));
        System.out.println(" ");
        //删除行
        rs.deleteRow();
        System.out.println("删除一条记录后ResultSet的内容...");
        printRs(rs);
        System.out.println("再见!");
    }
    public static void printRs(ResultSet rs) throws SQLException{
        //确保我们从第一行开始
        rs.beforeFirst();
        while(rs.next()){
            System.out.print("编号: " + rs.getInt("id"));
            System.out.print(", 工资: " + rs.getInt("Salary"));
            System.out.print(", 姓名: " + rs.getString("Name"));
            System.out.println(", 地址: " + rs.getString("Location"));
        }
        System.out.println();
    }
}

输出

Connection established......
Contents of the table:
ID: 1, Salary: 3000, Name: Amit, Location: Hyderabad
ID: 2, Salary: 4000, Name: Kalyan, Location: Vishakhapatnam
ID: 3, Salary: 6000, Name: Renuka, Location: Delhi
ID: 4, Salary: 9000, Name: Archana, Location: Mumbai
ID: 5, Salary: 11000, Name: Sumith, Location: Hyderabad
Conetnets of the resultset after increaing salaries
ID: 1, Salary: 8000, Name: Amit, Location: Hyderabad
ID: 2, Salary: 9000, Name: Kalyan, Location: Vishakhapatnam
ID: 3, Salary: 11000, Name: Renuka, Location: Delhi
ID: 4, Salary: 14000, Name: Archana, Location: Mumbai
ID: 5, Salary: 16000, Name: Sumith, Location: Hyderabad
Record we need to delete:
ID: 2, Salary: 9000, Name: Kalyan, Location: Vishakhapatnam
Contents of the resultset after deleting one records...
ID: 1, Salary: 8000, Name: Amit, Location: Hyderabad
ID: 3, Salary: 11000, Name: Renuka, Location: Delhi
ID: 4, Salary: 14000, Name: Archana, Location: Mumbai
ID: 5, Salary: 16000, Name: Sumith, Location: Hyderabad
Goodbye!