SQL Server - Group by - Additional column - sql

Question

I have a problem that I can hardly put in words and thus was not able to search for a solution before creating this post. Please forgive me if this has been asked before. Let me illustrate input and desired output:
Order Description Operation OperationDescription SubTarget
12 Order12 Op1 Order12, Op1 ABA
12 Order12 Op2 Order12, Op2 ABB
18 Order18 Op1 Order18, Op1 XYA
18 Order18 Op2 Order18, Op2 XYB
19 Order19 Op1 Order19, Op1 KLA
20 Order20 Op1 Order20, Op1 Truck123
20 Order20 Op2 Order20, Op2 Truck456
20 Order20 Op3 Order20, Op3 Truck789
20 Order20 Op4 Order20, Op4 Truck123
When I query the table above and group by Order and Description, I'd like to get all char from SubTarget (from left to write) as long as they match (and discard the rest):
Order Description SubTarget
12 Order12 AB
18 Order18 XY
19 Order19 KLA
20 Order20 Truck
I once found some neat code on the net to concatenate different values from a column not in the group by clause, using STUFF and FOR XML PATH. Not sure if that approach could be helpful here as well.
Thank you all in advance!
Regards,
Toby
Additional notes, based on comments and answer from #junketsu:
There is a column Target in the background, which is not accessible. Its content is always a partition of SubTarget - the other way around: SubTarget further adds some details to Target by adding more characters to the end of the string. That said, both values are not limited to two or three characters respectively. If so, I could easily use substring function.
The thrid example (Order# 19) might be confusing. I included this sample so show that it would be fine to the the whole string as a result if there were only one single operation in the order.
Another example may be: Order 5 with Operation Op1, Op2, Op3 and SubTarget Truck123, Truck456, Truck789 and Truck 123. This should produce "Truck" as outcome. The repetition of Truck123 is no error.
Hope this makes it clearer.
In the end I want to approach the actual content of column Target as it cannot be included in the query.
Thanks again,
Toby

Answer 1

I cant able to understand your Additional notes and The thrid example (Order# 19). I just worked for your expected answer,
create table #group (Orders int,Description varchar (20),Operation varchar (20)
,OperationDescription varchar (20),SubTarget varchar (20)
)
insert into #group values
(20,'Order20','Op1','Order20, Op1','Truck123')
,(20,'Order20','Op2','Order20, Op2','Truck456')
,(20,'Order20','Op3','Order20, Op3','Truck789')
,(20,'Order20','Op4','Order20, Op4','Truck123')
,(12,'Order12','Op1','Order12 Op1','ABA')
,(12,'Order12','Op2','Order12 Op2','ABB')
,(18,'Order18','Op1','Order18 Op1','XYA')
,(18,'Order18','Op2','Order18 Op2','XYB')
,(19,'Order19','Op1','Order19 Op1','KLA')
select distinct
gor.Orders, gor.Description, iif (g.c = 1, gor.SubTarget
, left (gor.subtarget, 2)) subtraget
from (
select distinct
orders, Description
, count (*) c
from #group group by orders, Description
) g join #group gor on g.Orders = gor.Orders
And I got :
Orders Description subtraget
12 Order12 AB
18 Order18 XY
19 Order19 KLA
20 Order20 Tr
Revert me, if query needs updates.
Update 1 Find the updated query.
select distinct
orders, Description, Operation, OperationDescription
, iif (count (*) over (partition by orders, Description ) = 1, subtarget,
left (subtarget, 2)
) subtarget
from #group
Update 2
1). cte: First of all I take a sub-string of all subtarget.
eg: Truck123->Truck12->Truck1->......->Tr.
2). countlen: I count the pattern in cte and get max length. Because, basic string comes many times.
eg: Truck comes more time than, Trunck123, Trunck456, Trunck789, Trunck123.
And Truck length is greater than Tr, Tru, Truc.
3). maxcount: I get the maximum count, which are returned by countlen
4). At last I join above cte's without subtarget. Then which is got from cte.
;with cte as (
select Orders, Description, SubTarget, len (SubTarget) len from #group
union all
select Orders, Description, left (subtarget, len (SubTarget) - 1)
, LEN (SubTarget) - 1 from cte where len > 2
), countlen as (
select
Orders, Description, SubTarget
, count (len) over (partition by Orders, Description, SubTarget order by len) count
, max (len) over (partition by Orders, Description, SubTarget order by len) maxlen
from cte
), maxcount as (
select Orders, Description, max (count) maxcount from countlen group by Orders, Description
) select distinct
o.Orders, o.Description, c.SubTarget
from (
select
cc.Orders, cc.Description, max (cc.maxlen) maxofmax
from countlen cc
join maxcount m
on cc.Orders = m.Orders and cc.Description = m.Description
where m.maxcount = cc.count
group by cc.Orders, cc.Description
) o
join cte c
on o.Orders = c.Orders and o.Description = c.Description and len (c.SubTarget) = o.maxofmax

Answer 2

Here you go good sir
create table #temp_1
( [order] int null
,Description varchar(15) null
,Operation varchar(30) null
,OperationDescription varchar(30) null
,SubTarget varchar(30) null
)
insert into #temp_1 values
(12 ,'Order12','Op1', 'Order12, Op1' ,'ABA')
,(12 ,'Order12',' Op2', 'Order12, Op2' ,'ABB')
,(18 ,'Order18','Op1', 'Order18, Op1' ,'XYA')
,(18 ,'Order18','Op2', 'Order18, Op2' ,'XYB')
,(19 ,'Order19','Op1', 'Order19, Op1' ,'KLA')
select *
from (
select *
,Rank_1 = Row_number() over(partition by SubTarget_1 order by [Order] asc)
from (
select [order],[Description]
--,SubTarget = substring(SubTarget,0,3)
,SubTarget_1 = case when SubTarget like 'a%b%' then 'AB'
when SubTarget like 'x%y%'then 'XY' else SubTarget end
from #temp_1
) a
) b
where Rank_1 = 1
order by [Order] asc