SAP HANA SQL 查询以查找两列之间的所有可能组合

Question

The target is to create all possible combinations of joining the two columns using SAP HANA SQL . every article of the first column ('100','101','102','103') must be in the combination result.

Sample Code

create table basis
(article Integer,
supplier VarChar(10) );
Insert into basis Values (100, 'A');
Insert into basis Values (101, 'A');
Insert into basis Values (101, 'B');
Insert into basis Values (101, 'C');
Insert into basis Values (102, 'D');
Insert into basis Values (103, 'B');

Result set

combination_nr;article;supplier
1;100;'A'
1;101;'A'
1;102;'D'
1;103;'B'
2;100;'A'
2;101;'B'
2;102;'D'
2;103;'B'
3;100;'A'
3;101;'C'
3;102;'D'
3;103;'B'

Let suppose if we add one more row against 102 as 'A' then our result set will be like this

Also according to the below-given calculations now we have 24 result sets

1;100;'A'
1;101;'A'
1;102;'A'
1;103;'B'

2;100;'A'
2;101;'A'
2;102;'D'
2;103;'B'

3;100;'A'
3;101;'B'
3;102;'A'
3;103;'B'

4;100;'A'
4;101;'B'
4;102;'D'
4;103;'B'

5;100;'A'
5;101;'C'
5;102;'A'
5;103;'B'

6;100;'A'
6;101;'C'
6;102;'D'
6;103;'B'

Calculations:

article 100: 1 supplier ('A')
article 101: 3 suppliers ('A','B','C')
article 102: 1 supplier ('D')
article 103: 1 supplier ('B')
unique articles: 4 (100,101,102,103)
1x3x1x1 x 4 = 12 (combination rows)

Answer 1

How about:

select article, 
       count(supplier) as nb_supplier,
       STRING_AGG(supplier,',') as list_suppliers
from (select distinct article, supplier from basis)
group by article