[LeetCode601] Human Traffic of Stadium

방문자수가 100이 넘는, id가 연속으로 3 이상인 경우만 나타내보려고 한다. 

lead와 leg를 사용하여 케이스를 만든다. 

select id, visit_date, people 
from (select id, visit_date, people,
            lead(people, 1) over (order by id) as after1,
            lead(people, 2) over (order by id) as after2,
            lag(people, 1) over (order by id) as pre1,
            lag(people, 2) over (order by id) as pre2    
      from stadium) as A
where A.people>99 and ((A.after1>99 and A.after2>99)
                        or (A.pre1 > 99 and A.pre2> 99)
                        or (A.pre1> 99 and A.after1 > 99)  );