1.从客户表中选取所有的客户,根据first_name的字母进行排序
    SELECT
    FROM customers
    *ORDER BY
    first_name

    2.从客户表中选取所有的客户,根据first_name的字母进行降序
    排序
    SELECT
    FROM customers
    ORDER BY first_name *DESC

    3.从客户表中选取所有的客户,根据first_name的字母进行升序
    排序
    SELECT
    FROM customers
    ORDER BY first_name *ASC

    4.从客户表中选取所有的客户,先根据所处州名排序,再根据
    first_name的字母进行降序排序
    SELECT
    FROM customers
    ORDER BY state, first_name *DESC

    MYSQL限定使用:
    5.从客户表内选择用户的first_name和last_name
    根据出生日期进行排序
    SELECT first_name, last_name
    FROM customers
    ORDER BY brith_date

    6.从客户表内选择用户的first_name和last_name
    以及新建的points列
    根据出生日期进行排序
    SELECT first_name, last_name,10 AS points
    FROM customers
    ORDER BY points, brith_date

    7.从客户表内选择用户的first_name和last_name
    以及新建的points列
    根据first_name, last_name进行排序
    这里使用了1, 2对列名进行代指
    SELECT first_name, last_name,10 AS points
    FROM customers
    ORDER BY 1, 2

    8.从订单表中选择ID为2的订单,并且根据product
    的总价格进行排序
    SELECT order_id, product_id, quantity * unit_price AS total_price
    FROM order_items
    WHERE order_id = 2
    ORDER BY total_price DESC