题目描述

编写一个 SQL 查询，查找所有至少连续出现三次的数字。

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+----+-----+
| 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。

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

解题思路

sql代码

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select distinct a.num as ConsecutiveNums
from logs as a, logs as b, logs as c
where a.id = b.id + 1 and a.id = c.id + 2 and
      a.Num = b.Num and a.Num = c.Num