如何获取具有不同列值的SQL条目

对。只使用 group by 和 having :

select key
from t
group by key
having min(attribute) <> max(attribute);

如果您想要详细的键/属性对,那么我建议您 exists :

select t.*
from t
where exists (select 1
              from t t2
              where t2.key = t.key and t2.attribute <> t.attribute
             );