LeetCode Database(196,197,262)

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196. Delete Duplicate Emails

末尾加上分号就Time Limit Exceeded

delete p1
from Person as p1, Person as p2
where p1.Id > p2.Id and p1.Email = p2.Email

delete p1
from Person p1
inner join Person p2
on p1.Email = p2.Email and p1.ID > p2.ID;

197. Rising Temperature

select w1.Id 
from Weather w1, Weather w2
where TO_DAYS(w1.Date) = TO_DAYS(w2.Date)+1 and w1.Temperature > w2.Temperature;

select w1.Id
from Weather w1 inner join Weather w2
on TO_DAYS(w1.Date) = TO_DAYS(w2.Date)+1 and w1.Temperature > w2.Temperature;

262. Trips and Users

select t.Request_at Day, 
        round(sum(
            case
                when t.Status like 'cancelled%' then 1 else 0
            END)/count(*), 2) 'Cancellation Rate'
from Trips t join Users u
on t.Client_Id = u.Users_Id and u.Banned = 'No'
where t.Request_at between '2013-10-01' and '2013-10-03' group by t.Request_at;

select Request_at Day,
        round(count(if(Status != 'completed', true, NULL)) / count(*), 2) 'Cancellation Rate'
from Trips
where (Request_at between '2013-10-01' and '2013-10-03') and Client_Id
in (select Users_Id from Users where Banned = 'No') group by Request_at;