mysql> EXPLAIN SELECT COUNT(DISTINCT(st.id)) FROM ticket st INNER JOIN queue sq ON sq.id = st.queue_id INNER JOIN ticket_history th ON st.id = th.ticket_id WHERE 1=1 AND sq.group_id IN (14,15,16,19,20) AND th.history_type_id IN (1, 27) AND th.state_id IN (10, 2, 3) AND th.create_time <= '2018-01-26...