Lc180-连续出现的数字

编写一个 SQL 查询，查找所有至少连续出现三次的数字。

+----+-----+
| Id | Num |
+----+-----+
| 1  |  1  |
| 2  |  1  |
| 3  |  1  |
| 4  |  2  |
| 5  |  1  |
| 6  |  2  |
| 7  |  2  |
+----+-----+
例如，给定上面的 Logs 表， 1 是唯一连续出现至少三次的数字。

+-----------------+
| ConsecutiveNums |
+-----------------+
| 1               |
+-----------------+

来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/consecutive-numbers
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# Write your MySQL query statement below、

select distinct(l1.num) as ConsecutiveNums 
from logs  l1
left join logs l2
on l1.num = l2.num
left join logs l3
on l2.num = l3.num
where l1.id = l2.id+1 
and l2.id = l3.id+1