52.sql

-- Question 52
-- 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
select distinct a.num as ConsecutiveNums
from(
select *,
lag(num) over() as prev,
lead(num) over() as next
from logs) a
where a.num = a.prev and a.num=a.next