Which gender logged in the most to an event in the first 10 days of May 2016?
gender that logged in the most refers to MAX(COUNT(gender)); first 10 days of May 2016 refers to timestamp BETWEEN '2016-05-01 00:00:00' AND '2016-05-10 23:59:59';
SELECT T.gender FROM ( SELECT T1.gender, COUNT(T1.device_id) AS num FROM gender_age AS T1 INNER JOIN events_relevant AS T2 ON T1.device_id = T2.device_id WHERE date(T2.timestamp) BETWEEN '2016-05-01' AND '2016-05-10' GROUP BY T1.gender ) AS T ORDER BY T.num DESC LIMIT 1