SQL concat function, combine size and colour - sql

Question

If there is a table called variant
id slug slug_id
------- --------- ----------
1 s 10
1 m 10
1 l 10
1 black 11
1 pink 11
1 ship_us 12
1 ship_uk 12
2 xl 10
2 xxl 10
2 blue 11
2 white 11
Result I need in this format:
id variant_slug
-------- ------------
1 1-s-black-ship_us
1 1-s-black-ship_uk
1 1-s-pink-ship_us
1 1-s-pink-ship_uk
1 1-m-black-ship_us
1 1-m-black-ship_uk
1 1-m-pink-ship_us
1 1-m-pink-ship_uk
1 1-l-black-ship_us
1 1-l-black-ship_uk
1 1-l-pink-ship_us
1 1-l-pink-ship_uk
2 2-xl-blue
2 2-xl-white
2 2-xxl-blue
2 2-xxl-white
Q: this record is in same variant table. I have almost no experience using UDFs, stored procedures, I need to be done this thing through query. Is this possible without using UDFs, SP's.

Answer 1

Perhaps a self-join assuming the length of size<=3.
Select A.ID
,variant_slug = concat(A.id,'-',A.slug,'-',B.slug)
from YourTable A
Join YourTable B
on A.ID=B.ID
and A.slug<>B.slug
and len(B.slug)>3
and len(A.slug)<=3
Results
ID variant_slug
1 1-l-black
1 1-l-pink
1 1-m-black
1 1-m-pink
1 1-s-black
1 1-s-pink
2 2-xl-blue
2 2-xl-white
2 2-xxl-blue
2 2-xxl-white
Rather than len(), you can enumerate the sizes i.e. {NOT } IN ('s','m','l','xl','xxl')
Select A.ID
,variant_slug = concat(A.id,'-',A.slug,'-',B.slug)
from YourTable A
Join YourTable B
on A.ID=B.ID
and A.slug<>B.slug
and B.slug NOT IN ('s','m','l','xl','xxl')
and A.slug IN ('s','m','l','xl','xxl')

Answer 2

You can go for INNER JOIN by separating the table into two separate tables: size, color and get the variant data, as given below:
declare #slug table(id int, slug varchar(100))
insert into #slug values
(1,'s')
,(1,'m')
,(1,'l')
,(1,'black')
,(1,'pink')
,(2,'xl')
,(2,'xxl')
,(2,'blue')
,(2,'white');
SELECT size.id, CONCAT_WS('-',size.id,size.size, color.color) as variant_size
from (select id,slug as size from #slug where slug in ('s','m','l','xl','xxl') ) as size
INNER JOIN (select id,slug as color from #slug where slug NOT in ('s','m','l','xl','xxl') ) as COLOR
on color.id = size.id
id
variant_size
1
1-s-black
1
1-s-pink
1
1-m-black
1
1-m-pink
1
1-l-black
1
1-l-pink
2
2-xl-blue
2
2-xl-white
2
2-xxl-blue
2
2-xxl-white