select count(case Position when 'Manager' then 1 else null end)
from ...
select sum(case Position when 'Manager' then 1 else 0 end)
from ...
SELECT count(CASE WHEN gender = 'F' THEN 1 ELSE NULL END) women_count,
count(CASE WHEN gender = 'M' THEN 1 ELSE NULL END) men_count
FROM people;
SELECT colonne1, SUM(colonne2)
FROM nom_table
GROUP BY colonne1
HAVING fonction(colonne2) operateur valeur