How many events are there?
select count(*) from events
List the events that have participant details with 'Lupe Deckow'?
select * from participants where participant_details = 'Lupe Deckow'
What about the ones with 'Kenyatta Kuhn'?
select * from participants where participant_details = 'Kenyatta Kuhn'
Show the id of the events where the above participants did not participate.
select event_id from events except select t1.event_id from participants_in_events as t1 join participants as t2 on t1.participant_id = t2.participant_id where participant_details = 'Kenyatta Kuhn'