【SQL】180. Consecutive Numbers

Write a SQL query to find all numbers that appear at least three times consecutively.

+----+-----+
| Id | Num |
+----+-----+
| 1  |  1  |
| 2  |  1  |
| 3  |  1  |
| 4  |  2  |
| 5  |  1  |
| 6  |  2  |
| 7  |  2  |
+----+-----+

For example, given the above Logs table, 1 is the only number that appears consecutively for at least three times.

这个题之前做过,面试时候见的时候依然写错了。。。看来刷的次数要多点啊

1 # Write your MySQL query statement below
2 SELECT DISTINCT l1.Num AS ConsecutiveNums
3 FROM Logs AS l1,Logs AS l2,Logs AS l3
4 WHERE l1.Id+1=l2.Id AND l2.Id+1=l3.Id AND l1.Num=l2.Num AND l2.Num=l3.Num;

 

posted @ 2017-03-02 23:55  wilderness  阅读(207)  评论(0编辑  收藏  举报