SQL Alleen rijen selecteren waar meerdere relaties bestaan

Dit heet Relationele divisie

SELECT  a.name
FROM    parent a
        INNER JOIN rel b
            ON a.parent_ID = b.parent_ID
WHERE   b.prop_id IN (1,5)
GROUP BY a.name
HAVING COUNT(*) = 2

• SQLFiddle-demolink

UPDATE 1

if unieke beperking werd niet afgedwongen op prop_id voor elke parent_id , DISTINCT is nodig in dit geval.

SELECT  a.name
FROM    parent a
        INNER JOIN rel b
            ON a.parent_ID = b.parent_ID
WHERE   b.prop_id IN (1,5)
GROUP BY a.name
HAVING COUNT(DISTINCT b.prop_id) = 2