Java JDBC: Update Database Data

To modify database data, you can use JDBC to execute SQL statements. Below is a simple example code to demonstrate how to use JDBC to modify database data.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class UpdateDataExample {

    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String username = "root";
        String password = "password";

        try {
            // 创建数据库连接
            Connection connection = DriverManager.getConnection(url, username, password);

            // 创建Statement对象
            Statement statement = connection.createStatement();

            // 执行SQL语句来修改数据
            String sql = "UPDATE mytable SET column1 = 'new value' WHERE id = 1";
            int rowsAffected = statement.executeUpdate(sql);

            // 输出受影响的行数
            System.out.println("Rows affected: " + rowsAffected);

            // 关闭连接
            statement.close();
            connection.close();

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

In the above example, a database connection is first created, followed by creating a Statement object to execute the SQL statement UPDATE mytable SET column1 = ‘new value’ WHERE id = 1 to modify data. By calling the executeUpdate method, the update operation can be executed and the number of affected rows will be returned. Lastly, remember to close the connection.