Use a date based on field value - sql

Question

I need to find a way to relate two sets of orders. Essentially, and inbound versus outbound analysis for a report. A load balance to see when I need to organize more pickups or deliveries.
I need to pull the delivery_date when billing_group = 3
I need to pull the origin_date when billing_group = 4
Hope this made some sense. Thank you all!
select convert(varchar,Delivery_Date,101) as 'Delivery_Date',
convert(varchar,Origin_Date,101) as 'Origin_Date',
sum(case when billing_group = '3' then 1 else 0 end) as 'OR to WA',
sum(case when billing_group = '4' then 1 else 0 end) as 'WA to OR',
count(*) as Total_Orders
from orders
where Date >= dateadd(day, datediff(day, 0, GetDate()) - 30, 0) and
billing_group in ('3','4')
group by Date
order by date desc
Would it be possible to combine these two separate queries into one to provide a the following columns? date, OR to WA, and WA to OR (like in the example above) where the date (regardless of origin or delivery date is used
select convert(varchar,Delivery_Date,101) as 'Date',
sum(case when billing_group = '3' and delivery_date >= dateadd(day,datediff(day, 0, GetDate()) - 30, 0) then 1 else 0 end) as 'OR to WA'
from orders
where delivery_Date >= dateadd(day, datediff(day, 0, GetDate()) - 20, 0) and billing_group in ('3')
group by delivery_date
order by date desc
select convert(varchar,Origin_Date,101) as 'Date',
sum(case when billing_group = '4' and origin_date >= dateadd(day, datediff(day, 0, GetDate()) - 30, 0)then 1 else 0 end) as 'WA to OR'
from orders
where origin_Date >= dateadd(day, datediff(day, 0, GetDate()) - 20, 0) and billing_group in ('4')
group by origin_Date
order by date desc

Answer 1

I think you need to group by convert(varchar,Delivery_Date,101) instead of date.
When you use aggregate function you need to add non-aggregate colunms in group by.
select convert(varchar,Delivery_Date,101) as 'Delivery_Date',
sum(case when billing_group = '3' then 1 else 0 end) as 'OR to WA',
sum(case when billing_group = '4' then 1 else 0 end) as 'WA to OR',
count(*) as Total_Orders
from orders
where Date >= dateadd(day, datediff(day, 0, GetDate()) - 30, 0) and
billing_group in ('3','4')
group by convert(varchar,Delivery_Date,101)
order by date desc
EDIT
I saw you edit your question, you can try to use UNION ALL
SELECT * FROM (
select convert(varchar,Delivery_Date,101) as 'Date',
sum(case when billing_group = '3' and delivery_date >= dateadd(day,datediff(day, 0, GetDate()) - 30, 0) then 1 else 0 end) as 'OR to WA'
from orders
where delivery_Date >= dateadd(day, datediff(day, 0, GetDate()) - 20, 0) and billing_group in ('3')
group by delivery_date
UNION ALL
select convert(varchar,Origin_Date,101) as 'Date',
sum(case when billing_group = '4' and origin_date >= dateadd(day, datediff(day, 0, GetDate()) - 30, 0)then 1 else 0 end) as 'WA to OR'
from orders
where origin_Date >= dateadd(day, datediff(day, 0, GetDate()) - 20, 0) and billing_group in ('4')
group by origin_Date
) t1
ORDER BY Date desc