JDBC使用模板-蒲公英云

JDBC使用模板

//1.导入驱动jar包
    //2.注册驱动
    Class.forName("com.mysql.jdbc.Driver");
    //3.获取数据库连接对象
    Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/school", "root", "123456");
    //4.定义sql语句
    String sql = "update user set username = 'qiqi' where userId = 1";
    //5.获取执行sql的对象 Statement
    Statement stmt = conn.createStatement();
    //6.执行sql
    int count = stmt.executeUpdate(sql);
    //7.处理结果
    System.out.println(count);
    //8.释放资源
    stmt.close();
    conn.close();
public static void main(String[] args)  {
        Connection conn = null;
        Statement stmt = null;
        try {
            //1.导入驱动jar包
            //2.注册驱动
            Class.forName("com.mysql.jdbc.Driver");
            //3.获取数据库连接对象
            conn = DriverManager.getConnection("jdbc:mysql:///school", "root", "123456");
            //4.定义sql语句
            String sql1 = "update user set username = 'zhier' where userId = 2";
            String sql2 = "Insert into user(userId,username,password) values (3,'sansan','123456')";
            String sql3 = "delete from user where userId = 3";
            //5.获取执行sql的对象 Statement
            stmt = conn.createStatement();
            //6.执行sql
            int i = stmt.executeUpdate(sql3);
            //7.处理结果
            System.out.println(i);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }finally {
            //8.释放资源
//            stmt.close();
//            conn.close()
            if (stmt != null){
                try {
                    stmt.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
            if (conn != null){
                try {
                    conn.close();
                } catch (SQLException throwables) {
                    throwables.printStackTrace();
                }
            }
        }
    }