Reputation: 25
i use sql server and i have this table :
ID Date Amount
I need to write a query that returns only users that have made at least 3 consecutive purchases, each one larger than the other.
I know that i need to use partition_id and row_number but i dont know how to do it
Thank you in advance
Upvotes: 0
Views: 631
Reputation: 1269753
If you want three purchases in a row with increases in amount, then use lead()
to get the next amounts:
select t.*
from (select t.*,
lead(amount, 1) over (partition by id order by date) as next_date,
lead(amount, 2) over (partition by id order by date) as next2_amount
from t
) t
where next_amount > amount and next2_amount > next_amount;
I originally missed the "greater than" part of the question. If you wanted purchases on three days in a row, then:
If you want three days in a row and there is at most one purchase per day, then you can use:
select t.*
from (select t.*,
lead(date, 2) over (partition by id order by date) as next2_date
from t
) t
where next2_date = dateadd(day, 2, date);
If you can have duplicates on a date, I would suggest this variant:
select t.*
from (select t.*,
lead(date, 2) over (partition by id order by date) as next2_date
from (select distinct id, date from t) t
) t
where next2_date = dateadd(day, 2, date);
Upvotes: 1