Script help - count , total and avg - sql

Question

I have the following script, trying to count how many distinct customers are there , how many distinct orders , what is total of all orders under £15 and its's avg, total of orders above £20 and it's avg.
with consignments as
(select
[Sell-to Customer No_],
[Convert-to Document No_],
ic.[Shipping Agent Service Code],
[Pick Completed DateTime] as [Shipped DateTime],
ROUND((ic.[Amount Including VAT] + ic.Postage + ic.[Gift Wrap Price] +
ic.[Handling Fee] + ic.[Personalisation Fee]),2) as [Document Amount]
from dbo.[Temp$Consignment] ic inner join [dbo].
[Temp$Order] oh
on ic.[Owner Header GuID]=oh.[Order Guid]
where ic.[Shipping Agent Service Code]='secstan' and ic.[Pick Completed
DateTime] >= '2016-11-01T00:00:00.000' AND
ic.[Pick Completed DateTime] <= '2016-11-30T23:59:55.000' ),summary as
(select *,CASE WHEN [Document Amount] > 15 THEN 1 ELSE 0 END as 'Over15'
from consignments )select * from summary
I have working script like below, but as I am new to sql I am bit confused how to convert above script to below.
select amountclass,[Shipping Agent Service Code],
count(distinct [Sell-to Customer No_]) as Total_customers,
count(*) as Total_orders,
sum([Amount]) as total_revenue,
avg([Amount] * 1.0) as AOV
from
(
select [Sell-to Customer No_], oh.[Original Order No_], [Amount],ic.
[Shipping Agent Service Code],
case when [Amount] <= 20 then 'Under_20'
else 'Over_20'
end as amountclass
from [TBW_BI].[dbo].[Temp$Order] oh INNER JOIN [TBW_BI].[dbo].
[Temp$Consignment] IC
ON IC.[Owner Header GuID]=OH.[Order Guid]
where[order date] >= '2016-09-01' AND
[order date] <= '2016-09-30' AND [COUNTRY]='UNITED KINGDOM' and
[document type] like 'ord%' and ic.[Shipping Agent Service
Code]='secstan'
) dt
group by amountclass,[Shipping Agent Service Code]
order by amountclass,[Shipping Agent Service Code]

Answer 1

It looks like you have a query with a 2 Common Table Expressions (CTE) and you want to convert the CTE to a derived table. First, we can eliminate one of the CTEs.
summary as
(select *,CASE WHEN [Document Amount] > 15 THEN 1 ELSE 0 END as 'Over15'
from consignments )
select * from summary
The CTE for summary is unnecessary. We can convert that code to this:
select *,CASE WHEN [Document Amount] > 15 THEN 1 ELSE 0 END as 'Over15'
from consignments
Now, instead of using the consignments CTE; we can copy the sql code within it to create a derived table.
select *,CASE WHEN [Document Amount] > 15 THEN 1 ELSE 0 END as 'Over15'
from (
select [Sell-to Customer No_],
[Convert-to Document No_],
ic.[Shipping Agent Service Code],
[Pick Completed DateTime] as [Shipped DateTime],
ROUND((ic.[Amount Including VAT] + ic.Postage + ic.[Gift Wrap Price] +
ic.[Handling Fee] + ic.[Personalisation Fee]),2) as [Document Amount]
from dbo.[Temp$Consignment] ic
inner join [dbo].[Temp$Order] oh on ic.[Owner Header GuID]=oh.[Order Guid]
where ic.[Shipping Agent Service Code]='secstan'
and ic.[Pick Completed
DateTime] >= '2016-11-01T00:00:00.000'
AND
ic.[Pick Completed DateTime] <= '2016-11-30T23:59:55.000' ) as t