leetcode_180_連續出現的數字

leetcode 180 連續出現的數字

• 題目

  編寫一個 SQL 查詢，查找所有至少連續出現三次的數字。
  
  +----+-----+
  | Id | Num |
  +----+-----+
  | 1  |  1  |
  | 2  |  1  |
  | 3  |  1  |
  | 4  |  2  |
  | 5  |  1  |
  | 6  |  2  |
  | 7  |  2  |
  +----+-----+
  例如，給定上面的 Logs 表， 1 是唯一連續出現至少三次的數字。
  
  +-----------------+
  | ConsecutiveNums |
  +-----------------+
  | 1               |
  +-----------------+
  

• 解
  1. Id連續且Num相等

     select distinct s1.Num as ConsecutiveNums
     from Logs as s1, Logs as s2, Logs as s3
     where s1.Id = s2.Id -1 and s2.Id = s3.Id -1 and s1.Num = s2.Num and s2.Num = s3.Num;