https://dev.mysql.com/doc/refman /8.0/en/union.html a dit :

Dans votre cas, cela ressemble à ceci :

(select customer_id, points, state from customers where state = 'CA' order by points desc limit 3)
union
(select customer_id, points, state from customers where state = 'FL' order by points desc limit 3)

Vous voudrez peut-être également en savoir plus sur les Fonctions de la fenêtre一个> :

select customer_id, points, state
from (
  select customer_id, points, state, 
    row_number() over (partition by state order by points desc) as rownum
  from customers where state in ('CA','FL')
) as t
where rownum