mysql 的复杂顺序

Question

如果我有这样的table

+----+----------------+
| id | id_alternativo |
+----+----------------+
| 15 |        18      |      
+----+----------------+
| 16 |        0       |      
+----+----------------+
| 17 |        0       |      
+----+----------------+
| 18 |        0       |
+----+----------------+

如何让记录在 ID 15 之后显示 ID 18？

Answer 1

据我所知，只需使用 order by id (18, 15) 和您需要的任何其他 ID。

Answer 2

select id,id_alternativo  
from table_name
order by case id  when 15 Then 1
                  when 18 Then 2
                  when 16 Then 3
                  when 17 Then 4
          else 5
          end;

Answer 3

你可以这样使用命令：

SELECT id 
FROM mytab
ORDER BY IF(id=18,155,id*10);

样本

MariaDB []> select id from mytab;
+----+
| id |
+----+
|  1 |
|  2 |
|  3 |
|  4 |
|  9 |
| 10 |
| 11 |
| 12 |
| 13 |
| 14 |
| 15 |
| 16 |
| 17 |
| 18 |
| 19 |
+----+
15 rows in set (0.00 sec)

MariaDB []> SELECT id
    -> FROM mytab
    -> ORDER BY IF(id=18,155,id*10);
+----+
| id |
+----+
|  1 |
|  2 |
|  3 |
|  4 |
|  9 |
| 10 |
| 11 |
| 12 |
| 13 |
| 14 |
| 15 |
| 18 |
| 16 |
| 17 |
| 19 |
+----+
15 rows in set (0.00 sec)

MariaDB []>

Answer 4

查看 MySQL 文档，您可以在排序中使用多列并每列使用 DESC/ASC。

http://dev.mysql.com/doc/refman/5.7/en/order-by-optimization.html

如果我理解正确，您的查询将如下所示：

SELECT id, id_alternativo FROM table ORDER BY id_alternativo DESC, id DESC;

+------+----------------+
| id   | id_alternativo |
+------+----------------+
|   15 |             18 |
|   18 |              0 |
|   17 |              0 |
|   16 |              0 |
+------+----------------+

Answer 5

一个解决方案是使用这样的自连接：

select t.*
from
  yourtable t left join yourtable o
  on t.id = o.id_alternativo
order by
  coalesce(o.id, t.id), t.id

这会将所有备用 ID 放在主要 ID 之后（在本例中，18 将跟在 15 之后）。

请看一个fiddlehere。请注意，除非替代 ID 有另一个替代 ID（例如，如果 18 本身有另一个替代 ID），这将起作用，但这不能纯粹用 MySQL 解决，因为它还不支持递归查询。

Answer 6

抱歉，我使用了一个简单的示例，但我的 table 更复杂。 id_alternativo 可以是递归的（id 18 可以有一个 id_alternativo = 19）等等，并且 id_alternativo 不能是 table 上最高的 id 所以 ORDER BY id_alternativo DESC, id DESC 不起作用。这是我的 table:

的查询

SELECT 
    a.id, a.compatibile, a.id_alternativo
FROM
    ordini_righe AS a
WHERE
    intestazione IN (398010) AND a.canc = 0
        AND a.stato_ordine = 0

这是结果

+-------+-------------+----------------+
|  id   | compatibile | id_alternativo |
+-------+-------------+----------------+
|828924 |      0      |     828931     |
+-------+-------------+----------------+
|828925 |    828932   |        0       |
+-------+-------------+----------------+
|828926 |      0      |        0       |
+-------+-------------+----------------+
|828927 |      0      |        0       |
+-------+-------------+----------------+
|828931 |      0      |     828933     |
+-------+-------------+----------------+
|828932 |    828932   |        0       |
+-------+-------------+----------------+
|828933 |      0      |        0       |
+-------+-------------+----------------+

我不得不订购compatibile desc，然后通过id_alternativo 和id 之间的关系订购其他记录。所以我解决了使用像这样的新列

SELECT 
    a.id, a.compatibile, a.id_alternativo, IF(id_alternativo = 0, a.id, id_alternativo) ordine
FROM
    ordini_righe AS a
        JOIN
    locazioni AS b ON a.locazione = b.id
        JOIN
    stati_righe AS c ON a.stato_ordine = c.id
WHERE
    intestazione IN (398010) AND a.canc = 0
        AND a.stato_ordine = 0
ORDER BY compatibile DESC, ordine, a.id ASC

我得到了想要的结果

+-------+-------------+----------------+--------+
|  id   | compatibile | id_alternativo | ordine |
+-------+-------------+----------------+--------+
|828925 |    828932   |     828931     | 828925 |
+-------+-------------+----------------+--------+
|828932 |    828932   |        0       | 828932 |
+-------+-------------+----------------+--------+
|828926 |      0      |        0       | 828926 |
+-------+-------------+----------------+--------+
|828927 |      0      |        0       | 828927 |
+-------+-------------+----------------+--------+
|828924 |      0      |     828931     | 828931 |
+-------+-------------+----------------+--------+
|828931 |      0      |     828933     | 828933 |
+-------+-------------+----------------+--------+
|828933 |      0      |        0       | 828933 |
+-------+-------------+----------------+--------+

mysql 的复杂顺序

Complex order by mysql

mysql

sql-order-by