Find out what group id contains all relevant attributes in SQL

Question

So lets say in this case, the group that we have is groups of animals.

Lets say I have the following tables:

animal_id | attribute_id | animal
---------         


        

Answer 1

You can use group by and having:

with a as (
      select 1 as attribute_id from dual union all
      select 4 as attribute_id from dual
     )
select t.animal_id, t.animal
from t join
     a
     on t.attribute_id = a.attribute_id
group by t.animal_id, t.animal
having count(*) = (select count(*) from a);

The above will find all animals that have those attributes and any others. If you want animals that have exactly those 2 attributes:

with a as (
      select 1 as attribute_id from dual union all
      select 4 as attribute_id from dual
     )
select t.animal_id, t.animal
from t left join
     a
     on t.attribute_id = a.attribute_id
group by t.animal_id, t.animal
having count(*) = (select count(*) from a) and
       count(*) = count(a.attribute_id);