SELECT count(*) FROM participants AS T1 JOIN Participants_in_Events AS T2 ON T1.Participant_ID  =  T2.Participant_ID WHERE T1.participant_details LIKE '%Dr.%'
How many events had participants whose details had the substring 'Dr.'
SELECT count ( * ) FROM participants AS T1 JOIN Participants_in_Events AS T2 ON T1.Participant_ID = T2.Participant_ID WHERE T1.participant_details LIKE ' % Dr. % '
select count ( * ) from participants as t1 join participants_in_events as t2 on t1 . participant_id = t2 . participant_id where t1 . participant_details like value
How many events had participants whose details had the substring 'Dr . '