SQL selecting rows where one column's value is common across another criteria column

Question

I have a cross reference table that looks like this:

id  document_id  subject_id
1   8            21
2   5            17
3   5            76
4   7                    


        

Answer 1

Using Oracle (or any database that allows the with clause). This allows definition of the subject_id values exactly once.

with t as (select distinct document_id from table1 where subject_id in (17,76) )
select document_id from table1 where subject_id in (select subject_id from t)
group by document_id 
having count(*) = (select count (*) from t);