У меня есть следующий запрос
with cte1 as (
select isnull(A, 'Unknown') as A,
isnull(nullif(B, 'NULL'), 'Unknown') as B,
C
from ... -- uses collate SQL_Latin1_General_CP1_CI_AS when joining
group by isnull(A, 'Unknown'), isnull(nullif(B, 'NULL'), 'Unknown'), C
),
cte2 as (select top (2147483647) A, B, C from cte1 order by A, B, C),
-- Removing cte2 makes it work if running directly as SQL query. However,
-- it still behave the same if the code is in view or table function
ctes as (
.... -- pretty complex query joining cte2 multiple times
-- uses row_number(), ntile
)
select count(*) from finalCTE
Результат (количество) изменяется каждый раз при его выполнении. И это намного меньше, чем должно быть. Я нашел, что любой из следующих шагов может сделать это правильно.
- Составьте (временную или постоянную таблицу) CTE
cte1
и используйте вместо этого материализованную таблицу. - Измените группу на
cte1
на любую следующих форм.-
group by A, isnull(nullif(B, 'NULL'), 'Unknown'), C
-
group by isnull(A, 'Unknown'), nullif(B, 'NULL'), C
-
group by A, nullif(B, 'NULL'), C
- Используйте
cte1
вместоcte2
в других CTE. ( Обновление: Этот шаг не всегда работает. Тем не менее проблема связана с функцией таблицы, хотя она работает, если вы запускаете SQL напрямую)
-
Однако, почему исходный запрос ведет себя странно? Это ошибка в SQL Server?
Полный функциональный код:
ALTER function [dbo].[fn] (@para1 char(3))
returns table
return
with cte1 as ( select AAA, BBB, CCC
from dbo.fnBBB(12)
where @para1 = 'xxxx'
union all
select AAA, BBB, CCC
from dbo.fnBBB2(12)
where @para1 = 'yyyy'
),
-- Tested not using cte2, the same behave
cte2 as (select top (2147483647) AAA, BBB, CCC from cte1 order by AAA, BBB, CCC),
t as ( select e.CCC, e.value1, cte2.BBB, cte2.AAA
from dbo.T1 e
join cte2 on e.CCC = cte2.CCC
),
b as ( select BBB, AAA, count(*) count,
case when count(*) / 5 > 10 then 10
else count(*) / 5
end as buckets
from t
group by BBB, AAA
having count(*) >= 5
),
b2
as ( select t.*
from b
cross apply ( select *,
ntile(b.buckets) over ( partition by t.BBB, t.AAA order by value1, CCC )
as bucket
from t
where BBB = b.BBB
and AAA = b.AAA
) t
),
m1
as ( select AAA, BBB, b2.CCC, Date, SId, value2, b2.bucket, --
_asc = row_number() over ( partition by BBB, AAA, bucket, Date, SId order by value2, b2.CCC ),
_desc = row_number() over ( partition by BBB, AAA, bucket, Date, SId order by value2 desc, b2.CCC desc )
,count(*) over (partition by BBB, AAA, bucket, Date, SId) scount
from b2 join dbo.T2 e on b2.CCC = e.CCC
),
median
as ( select BBB, AAA, bucket, Date, SId, avg(value2) value2Median, min(scount) sCount
from m1
where _asc in ( _desc, _desc - 1, _desc + 1 )
group by BBB, AAA, bucket, Date, SId
),
bounds
as ( select BBB, AAA, bucket, min(value1) dboMin, max(value1) value1Max, count(*) count
from b2
group by BBB, AAA, bucket
)
select m.*, b.dboMin, b.value1Max, Count
from median m join bounds b on m.BBB = b.BBB and m.AAA = b.AAA and m.bucket = b.bucket
-- order by BBB, AAA, bucket
Функция, используемая в cte1:
CREATE function [dbo].[fnBBB](@param int)
returns table
return
with m as ( select * -- only this view has non default collate (..._CS_AS)
from dbo.view1 -- indxed view.
)
select isnull(g.AAA, 'Unknown') as AAA,
isnull(nullif(m1.value, 'NULL'), 'Unknown') as BBB
, m.CCC
from m
left join dbo.mapping m0 on m0.id = 12
and m0.value = m. v1 collate SQL_Latin1_General_CP1_CI_AS
left join dbo.map1 r on r.Country = m0.value
left join dbo.map2 g on g.N = r.N
left join dbo.mapping m1 on m1.id = 20
and m1.value = m.v2 collate SQL_Latin1_General_CP1_CI_AS
where m.run_date > dateadd(mm, [email protected], getdate())
group by isnull(g.AAA, 'Unknown'), isnull(nullif(m1.value, 'NULL'), 'Unknown'), m.CCC