SQL Select row depending on values in different columns

Question

I've already found so many answers here but now I can't seem to find any to my specific problem.

I can't figure out how to select a value from a row depending on the value in different columns

with the below table, I want to achieve the following results.

in case the value in column stdvpuni = 1 then return values / contents from this row for the article (column art).

in case the value in column stdvpuni = 0 then return values / contents from the row where STDUNIABG = 1 for this article (column art).

Answer 1

You seem to want one row part art, based on the content of other rows. That suggests using row_number():

select t.*
from (select t.*,
             row_number() over (partition by art order by stdvpuni desc, STDUNIABG desc) as seqnum
      from t
     ) t
where seqnum = 1;

You don't specify what to do if neither column is 1. You might want a where clause (where 1 in (stdvpuni, STDUNIABG)) or another condition in the order by.