How to use alias name with partition by in sql - sql

Question

I'm fetching record of players having categorized with golf handicaps. Like players having handicap between 0 to 5 lies in 0-5 range and similarly having handicap between 6-11 lies in the range of 6-11 and so on and so forth. What I'm trying is to fetch top 3 players from each range so that I can setup flights for each rounds.
I have used partition by clause to separate records and ROW_NUMBER to get top 3 players from each range. In order to define ranges, i have used multiple cases. Now how do i use range as alias name with partition by or any way that can generate the correct result. Below is my query.
select * from (
select uu.Id, firstname, lastname, userhandicap,
case when userhandicap>=0 and userhandicap<=5 then '0-5'
when userhandicap>=6 and userhandicap<=11 then '6-11'
when UserHandicap>=12 and UserHandicap<=18 then '12-18'
when UserHandicap>=19 and UserHandicap<=26 then '19-26'
else '27 and above' end as range, RN = ROW_Number() over (PARTITION BY
range order by cast(userhandicap as int))
from dbo.[User] uu inner join dbo.[EventRegisteredUsers] eru
on uu.Id = eru.UserId
where eru.UserId not in (Select fp.UserId from dbo.[FlightPlayer] fp
inner join dbo.[Flight] f
on fp.FlightId = f.Id
where f.Rounds = '1'
and f.Starthole = '0a9b926e-0baa-4369-8cf8-8fc84ca80d65' and f.EventId =
'7de10ad6-098d-419f-9c2d-2e62803ad1f7')
and eru.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7') uu
WHERE
uu.RN <= 3

Answer 1

You can use apply to define the range value within the subquery. This is the simplest method for defining the range:
select *
from (select uu.Id, firstname, lastname, userhandicap,
row_number() over (partition by v.range order by cast(userhandicap as int)) as seqnum
from dbo.[User] uu inner join
dbo.[EventRegisteredUsers] eru
on uu.Id = eru.UserId cross apply
(values (case when userhandicap <= 5 then '0-5'
when userhandicap <= 11 then '6-11'
when UserHandicap <= 18 then '12-18'
when UserHandicap <= 26 then '19-26'
else '27 and above'
end)
) v(range)
where not exists (select 1
from dbo.[FlightPlayer] fp join
dbo.[Flight] f
on fp.FlightId = f.Id
where eru.UserId = fp.UserId and
f.Rounds = '1' and
f.Starthole = '0a9b926e-0baa-4369-8cf8-8fc84ca80d65' and
f.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7'
) and
eru.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7'
) uu
where uu.seqnum <= 3;
Note other changes to the query:
Don't use not in with a subquery. If the subquery returns a NULL value, then all values are filtered out. That is not (usually) the expected behavior.
The case expression is overly complicated. Use the fact that case is guaranteed to evaluate the conditions in order.
You should qualify all column names in a query that has more than one query. However, it is unclear where the columns come from.
Presumably handicap is not ever negative, based on your original logic (and the rules of golf), so I am comfortable removing that condition.

Answer 2

use cte
with cte as
(
select uu.Id, firstname, lastname, userhandicap,
case when userhandicap>=0 and userhandicap<=5 then '0-5'
when userhandicap>=6 and userhandicap<=11 then '6-11'
when UserHandicap>=12 and UserHandicap<=18 then '12-18'
when UserHandicap>=19 and UserHandicap<=26 then '19-26'
else '27 and above' end as range
from dbo.[User] uu inner join dbo.[EventRegisteredUsers] eru
on uu.Id = eru.UserId
where eru.UserId not in (Select fp.UserId from dbo.[FlightPlayer] fp
inner join dbo.[Flight] f
on fp.FlightId = f.Id
where f.Rounds = '1'
and f.Starthole = '0a9b926e-0baa-4369-8cf8-8fc84ca80d65' and f.EventId =
'7de10ad6-098d-419f-9c2d-2e62803ad1f7')
and eru.EventId = '7de10ad6-098d-419f-9c2d-2e62803ad1f7'
), t2 as
(
select *,row_number() over(partition by range order by cast(userhandicap as int) rn from cte
) select * from t2 where rn<=3