【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;