Dear Experts,

I'm looking for a good technique to do "and" searches on one-to-many joined tables.  For example, to find people with both 'dark hair' and 'president':

# select * from test_people join test_attributes using (people_id);
+-----------+-------------+---------------+
| people_id | person_name |   attribute   |
+-----------+-------------+---------------+
|        10 | Satan       | The Devil     |
|         9 | Santa       | Imaginary     |
|         8 | Obamba      | Dark Hair     |
|         8 | Obamba      | Dark Hair     |
|         8 | Obamba      | USA President |
|        10 | Satan       | Dark Hair     |
+-----------+-------------+---------------+

# select person_name from test_people where people_id in
(select people_id from test_attributes where attribute='USA President' 
 INTERSECT
 select people_id from test_attributes where attribute='Dark Hair');

# select person_name from test_people
where people_id in
(select people_id from test_attributes where attribute='USA President')
and people_id in
(select people_id from test_attributes where attribute='Dark Hair');

# select people_id,count(*) as count from test_people
join test_attributes using (people_id)
where attribute='Dark Hair' or attribute='USA President'
group by people_id having count(*) >= 2;


A postgres specific solution is OK, but SQL92 is better.  I had the "in" solution recommended to me, but it's performing dramatically poorly on huge tables.

Thanks for any references to a solution!  -Bryce