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