SQL Server 2019

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select *
into t
from (values
     (4711, 'A'),
     (4712, 'B'),
     (4712, 'C'),
     (4712, 'D'),
     (4713, 'C'),
     (4713, 'E')
    ) v (article, supplier)
6 rows affected

with a as (
      select distinct article from t
     ),
     cte as (
      select a.article, 1 as lev, convert(varchar(max), article) as grp
      from a
      union all
      select a.article, lev + 1, concat(grp, ':', a.article)
      from cte join
           a
           on a.article > cte.article
     )
select cte.combination_number, s.value
from (select cte.*, row_number() over (order by lev, grp) as combination_number
      from cte
     ) cte cross apply
     string_split(grp, ':') s
order by cte.combination_number, s.value


combination_number
value


1
4711

2
4712

3
4713

4
4711

4
4712

5
4711

5
4713

6
4712

6
4713

7
4711

7
4712

7
4713


with a as (
      select distinct article, supplier from t
     ),
     cte as (
      select a.article, a.supplier, 1 as lev, convert(varchar(max), article) + '-' + supplier as grp
      from a
      union all
      select a.article, a.supplier, lev + 1, concat(grp, ':', a.article, '-' + a.supplier)
      from cte join
           a
           on a.article > cte.article
     )
select cte.combination_number,
       left(s.value, charindex('-', s.value) - 1) as article,
       stuff(s.value, 1, charindex('-', s.value), '') as supplier
from (select cte.*, row_number() over (order by lev, grp) as combination_number
      from cte
     ) cte cross apply
     string_split(grp, ':') s
order by cte.combination_number, s.value


combination_number
article
supplier


1
4711
A

2
4712
B

3
4712
C

4
4712
D

5
4713
C

6
4713
E

7
4711
A

7
4712
B

8
4711
A

8
4712
C

9
4711
A

9
4712
D

10
4711
A

10
4713
C

11
4711
A

11
4713
E

12
4712
B

12
4713
C

13
4712
B

13
4713
E

14
4712
C

14
4713
C

15
4712
C

15
4713
E

16
4712
D

16
4713
C

17
4712
D

17
4713
E

18
4711
A

18
4712
B

18
4713
C

19
4711
A

19
4712
B

19
4713
E

20
4711
A

20
4712
C

20
4713
C

21
4711
A

21
4712
C

21
4713
E

22
4711
A

22
4712
D

22
4713
C

23
4711
A

23
4712
D

23
4713
E
combination_number	value
1	4711
2	4712
3	4713
4	4711
4	4712
5	4711
5	4713
6	4712
6	4713
7	4711
7	4712
7	4713