我有一个名为users的简单表,其中包含以下数据：

id | hops
 1 | 3
 2 | 1
 3 | 5
 4 | 2
 5 | 6
 6 | 5

我想根据跳的降序进行上一个/下一个导航.我使用以下查询来对降序进行排序：

SELECT * FROM users ORDER BY hops DESC, id DESC

结果如下：

id | hops
 5 | 6
 6 | 5
 3 | 5
 1 | 3
 4 | 2
 2 | 1

现在我想要的是,当我在mysql查询中输入任何ID时,根据上述排序,我得到了上一个和下一个ID.例如：

对于id 5(在这种情况下,id = 5的跳数最高,因此之前没有任何记录)：

id (current) | hops (current) | id (prev) | hops (prev) | id (next) | hops (next)
   5         |    6           |  NULL     | NULL        |  6        |  5

对于ID 6：

id (current) | hops (current) | id (prev) | hops (prev) | id (next) | hops (next)
   6         |    5           |  5        |     6       |  3        |  5

对于ID 3：

id (current) | hops (current) | id (prev) | hops (prev) | id (next) | hops (next)
   3         |    5           |  6        |    5        |  1        |  3

对于ID 1：

id (current) | hops (current) | id (prev) | hops (prev) | id (next) | hops (next)
   1         |    3           |  3        |    5        |  4        |  2

对于ID 4：

id (current) | hops (current) | id (prev) | hops (prev) | id (next) | hops (next)
   4         |    2           |  1        | 3           |  2        |  1

对于id 2(在这种情况下,id = 2的跳数最低,因此之后没有后续记录)

id (current) | hops (current) | id (prev) | hops (prev) | id (next) | hops (next)
   2         |    1           |  4        | 2           |  NULL     |  NULL

谢谢

解决方法:

尝试：

select cp.*, n.id id_next, n.hops hops_next
from
(select c.id id_current, c.hops hops_current, p.id id_previous, p.hops hops_previous
 from
 (select * from users where id = ?) c
 left join users p on c.hops < p.hops or (c.id < p.id and c.hops = p.hops)
 order by p.hops, p.id limit 1) cp 
left join users n 
       on cp.hops_current > n.hops or (cp.id_current > n.id and cp.hops_current = n.hops)
order by n.hops desc, n.id desc limit 1

(SQLFiddle here)