Problem
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.
+-----------------+
| ConsecutiveNums |
+-----------------+
| 1 |
+-----------------+
Solution 1
# Write your MySQL query statement below
select distinct A.Num as ConsecutiveNums
from Logs A
left join logs B
on A.Id = B.Id - 1
left join logs C
on B.Id = C.Id - 1
where A.Num = B.Num
and B.Num = C.Num
Explain:
nope.
Complexity:
- Time complexity :
- Space complexity :
Solution 2
# Write your MySQL query statement below
select distinct A.Num as ConsecutiveNums
from Logs A, logs B, logs C
where A.Num = B.Num
and B.Num = C.Num
and A.Id = B.Id - 1
and B.Id = C.Id - 1
Explain:
nope.
Complexity:
- Time complexity :
- Space complexity :