JZTXT

通过JDBC访问Mysql

发布时间 2023-06-12 01:16:54作者: 妖妖领先

1.JDBC访问Mysql示例

查询语句
public class JdbcFirstDemo {
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        // 1.载入jdbc驱动
        Class.forName("com.mysql.cj.jdbc.Driver");

        // 2.配置基本信息
        String url = "jdbc:mysql://localhost:3306/workdb?useUnicode=true&characterEncoding=utf8&useSSL=true";
        String username = "root";
        String password = "Wcj920615*";

        // 3.获取数据库连接对象
        Connection connection = DriverManager.getConnection(url, username, password);

        // 4.创建sql对象
        Statement statement = connection.createStatement();

        // 5.执行查询sql
        String sql = "select * from t_students";
        ResultSet resultSet = statement.executeQuery(sql);
        while (resultSet.next()) {
            System.out.println(resultSet.getObject("id"));
            System.out.println(resultSet.getObject("name"));
            System.out.println(resultSet.getObject("gender"));
            System.out.println(resultSet.getObject("grade"));
            System.out.println(resultSet.getObject("score"));
            System.out.println("====================================");
        }
    }
}

结果：
image

插入语句
        // 6.插入语句
        String sql2 = "insert into t_students (`name`, `gender`, `grade`,`score`,`student_no`) values ('小明','2','4',95,6)";
        int res = statement.executeUpdate(sql2);
        if (res >= 1) {
            System.out.println("insert successful.");
        } else {
            System.out.println("error.");
        }

截图：
image

更新语句
        // 7. 更新语句
        String sql3 = "update t_students set score = 100 where id = 21";
        int res = statement.executeUpdate(sql3);
        if (res >= 1) {
            System.out.println("update successful.");
        } else {
            System.out.println("error.");
        }

截图：
image

删除语句
        // 8. 删除语句
        String sql4 = "delete from t_students where id = 21";
        int res = statement.executeUpdate(sql4);
        if (res >= 1) {
            System.out.println("delete successful.");
        } else {
            System.out.println("error.");
        }

截图：
image