How many male users are active in the events held on 5/1/2016?
male refers to gender = 'M'; active refers to is_active = 1; on 5/1/2016 refers to timestamp LIKE '2016-05-01%';
SELECT COUNT(T3.gender) FROM app_events AS T1 INNER JOIN events_relevant AS T2 ON T2.event_id = T1.event_id INNER JOIN gender_age AS T3 ON T3.device_id = T2.device_id WHERE T1.is_active = 1 AND T3.gender = 'M' AND T2.timestamp LIKE '2016-05-01%'