我在数据库toto上有一个products表，看起来像这样：

MariaDB [toto]> desc products;
+------------+--------------+------+-----+---------+-------+
| Field      | Type         | Null | Key | Default | Extra |
+------------+--------------+------+-----+---------+-------+
| id         | int(11)      | NO   | PRI | NULL    |       |
| product_id | int(11)      | NO   |     | NULL    |       |
| sold_at    | datetime     | YES  |     | NULL    |       |
| rate       | int(11)      | YES  |     | NULL    |       |
| name       | varchar(128) | NO   |     | NULL    |       |
+------------+--------------+------+-----+---------+-------+

现在我承认这些数据：

MariaDB [toto]> select * from products;
+----+------------+---------------------+----------+-----------+
| id | product_id | sold_at             | rate     | name      |
+----+------------+---------------------+----------+-----------+
|  1 |        400 | 2023-04-14 07:28:44 |     NULL | product_1 |
|  2 |        399 | NULL                |      728 | product_2 |
|  3 |        401 | 2023-04-14 07:28:44 |   100000 | product_3 |
|  4 |        398 | NULL                | 99999999 | product_4 |
|  5 |        404 | 2023-04-14 07:45:00 |        1 | product_5 |
+----+------------+---------------------+----------+-----------+
5 rows in set (0.001 sec)

我的目标是按rate DESC对所有这些结果进行排序，所有产品的sold_at值首先不是null，这意味着我希望所有非null sold_at等于1，null sold_at为0。看起来像这样：

+----+------------+---------------------+----------+-----------+
| id | product_id | sold_at             | rate     | name      |
+----+------------+---------------------+----------+-----------+
|  3 |        401 | 2023-04-14 07:28:44 |   100000 | product_3 |
|  5 |        404 | 2023-04-14 07:45:00 |        1 | product_5 |
|  1 |        400 | 2023-04-14 07:28:44 |     NULL | product_1 |
|  4 |        398 | NULL                | 99999999 | product_4 |
|  2 |        399 | NULL                |      728 | product_2 |
+----+------------+---------------------+----------+-----------+

请注意，某些产品的sold_at速率可能为NULL。

我目前尝试了多种方法，但都没有效果，例如：

WITH data AS (SELECT * FROM products ORDER BY rate DESC) SELECT * FROM data ORDER BY sold_at;

SELECT * FROM products ORDER BY rate DESC, sold_at ASC;

我知道为什么这不起作用（因为sold_at目前正在订购太使用它的日期，但我不知道如何做到）。