Query to find Cumulative while subtracting other counts - sql

Question

Here is my table structure
Id INT
RecId INT
Dated DATETIME
Status INT
and here is my data.
Status table (contains different statuses)
Id Status
1 Created
2 Assigned
Log table (contains logs for the different statuses that a record went through (RecId))
Id RecId Dated Status
1 1 2013-12-09 14:16:31.930 1
2 7 2013-12-09 14:27:26.620 1
3 1 2013-12-09 14:27:26.620 2
3 8 2013-12-10 11:14:13.747 1
3 9 2013-12-10 11:14:13.747 1
3 8 2013-12-10 11:14:13.747 2
What I need to generate a report from this data in the following format.
Dated Created Assigned
2013-12-09 2 1
2013-12-10 3 1
Here the rows data is calculated date wise. The Created is calculated as (previous record (date) Created count - Previous date Assigned count) + Todays Created count.
For example if on date 2013-12-10 three entries were made to log table out of which two have the status Created while one has the status assigned. So in the desired view that I want to build for report, For date 2013-12-10, the view will return Created as 2 + 1 = 3 where 2 is newly inserted records in log table and 1 is the previous day remaining record count (Created - Assigned) 2 - 1.
I hope the scenario is clear. Please ask me if further information is required.
Please help me with the sql to construct the above view.

Answer 1

This matches the expected result for the provided sample, but may require more testing.
with CTE as (
select
*
, row_number() over(order by dt ASC) as rn
from (
select
cast(created.dated as date) as dt
, count(created.status) as Created
, count(Assigned.status) as Assigned
, count(created.status)
- count(Assigned.status) as Delta
from LogTable created
left join LogTable assigned
on created.RecId = assigned.RecId
and created.status = 1
and assigned.Status = 2
and created.Dated <= assigned.Dated
where created.status = 1
group by
cast(created.dated as date)
) x
)
select
dt.dt
, dt.created + coalesce(nxt.delta,0) as created
, dt.assigned
from CTE dt
left join CTE nxt on dt.rn = nxt.rn+1
;
Result:
| DT | CREATED | ASSIGNED |
|------------|---------|----------|
| 2013-12-09 | 2 | 1 |
| 2013-12-10 | 3 | 1 |
See this SQLFiddle demo