Replace null value with previous value - SQL Server 2008 R2 - replace

Question

Will post this question again with full code. Last try I didn't write it all which resulted in answers that I could not use.
I have below query and want to replace the latest NULL-value with previous value for that currency. Sometimes there are many null-values on the same date and sometimes there is only one.
I guess I have to do something with the left join on cteB? Any ideas?
See result and desired result below query
With cte as (
SELECT
PositionDate,
c.Currency,
DepositLclCcy
FROM
[Static].[tbl_DateTable] dt
CROSS JOIN (Values ('DKK'), ('EUR'), ('SEK')) as c (Currency)
Left join
(
SELECT
BalanceDate,
Currency,
'DepositLclCcy' = Sum(Case when Activity = 'Deposit' then BalanceCcy else 0 END)
FROM
[Position].[vw_InternalBank]
Group By
BalanceDate,
Currency
) ib
on dt.PositionDate = ib.BalanceDate
and c.Currency = ib.Currency
Where
WeekDate = 'Yes')
Select
*
From cte cteA
Left join
( Select ... from Cte ) as cteB
on .....
Order by
cteA.PositionDate desc,
cteA.Currency
Current Result
PositionDate Currency DepositLclCcy
2017-04-11 SEK 1
2017-04-11 DKK 3
2017-04-11 EUR 7
2017-04-10 SEK NULL
2017-04-10 DKK 3
2017-04-10 EUR 5
2017-04-07 SEK 5
2017-04-07 DKK 3
2017-04-07 EUR 5
Desired Result
PositionDate Currency DepositLclCcy
2017-04-11 SEK 1
2017-04-11 DKK 3
2017-04-11 EUR 7
2017-04-10 SEK 5
2017-04-10 DKK 3
2017-04-10 EUR 5
2017-04-07 SEK 5
2017-04-07 DKK 3
2017-04-07 EUR 5

Answer 1

using outer apply() to get the previous value for DepositLclCcy, and replacing null values using coalesce().
with cte as (
select
PositionDate
, c.Currency
, DepositLclCcy
from [Static].[tbl_DateTable] dt
cross join (values ('DKK') , ('EUR') , ('SEK')) as c(Currency)
left join (
select
BalanceDate
, Currency
, DepositLclCcy = Sum(case when Activity = 'Deposit' then BalanceCcy else 0 end)
from [Position].[vw_InternalBank]
group by BalanceDate, Currency
) ib
on dt.PositionDate = ib.BalanceDate
and c.Currency = ib.Currency
where WeekDate = 'Yes'
)
select
cte.PositionDate
, cte.Currency
, DepositLclCcy = coalesce(cte.DepositLclCcy,x.DepositLclCcy)
from cte
outer apply (
select top 1 i.DepositLclCcy
from cte as i
where i.PositionDate < cte.PositionDate
and i.Currency = cte.Currency
order by i.PositionDate desc
) as x
Skipping the initial left join and using outer apply() there instead:
with cte as (
select
dt.PositionDate
, c.Currency
, ib.DepositLclCcy
from [Static].[tbl_DateTable] dt
cross join (values ('DKK'), ('EUR'), ('SEK')) as c(Currency)
outer apply (
select top 1
DepositLclCcy = sum(BalanceCcy)
from [Position].[vw_InternalBank] as i
where i.Activity = 'Deposit'
and i.Currency = c.Currency
and i.BalanceDate <= dt.PositionDate
group by i.BalanceDate, i.Currency
order by i.BalanceDate desc
) as ib
where dt.WeekDate = 'Yes'
)
select *
from cte